promotional website at defendingbitcoin.com<\/a> that the author promises to keep updated in the fast-changing landscape of software and security breaches.<\/p>\n\n\n\n<\/p>\n\n\n\n
De Wolf\u2019s unique niche is his professional background in industrial control systems (ICS) \u2014 the kind of software and informational processes that safeguard societal-level, critical infrastructure. Think power plants and gas pipelines, water systems or telecommunication. He treats Bitcoin as the society-critical infrastructure that it is, or at least will be (\u201cBitcoin isn\u2019t a factory or a pipeline, but like them, it has to keep running, no matter what\u201d, page 86).<\/p>\n\n\n\n
<\/p>\n\n\n\n
The introductory Bitcoin explainer is a bit rushed: unnecessary for the Bitcoin crowd and probably not detailed enough for the corporate security folks de Wolf is trying to sway. Still, it\u2019s very<\/em> competently done: correct, succinct, relevant \u2014 no qualms in recommending this book for an interested newcomer. <\/p>\n\n\n\n<\/p>\n\n\n\n
<\/p>\n\n\n\n
Laying out the framework for how to think about cybersecurity fundamentals (Ch 3) and ICSs (Ch 4) before moving on to the specific threat surfaces that apply to Bitcoin, grounds the mental models de Wolf uses. It\u2019s balanced and careful, and both novel and surprisingly relatable to most Bitcoiners: \u201cAsk yourself what you\u2019re protecting, what it\u2019s worth, and how much friction you\u2019re willing to tolerate to defend it. That decision is yours\u201d (page 63).
<\/p>\n\n\n\n
<\/p>\n\n\n\n
<\/p>\n\n\n\n
The core of his framework is layered defenses and appropriate tradeoffs against multifaceted threats \u2014 \u201cexpected value\u201d and \u201cmarginal costs vs marginal benefits\u201d echo through my economics-trained head. Every additional defense comes with costs in creating it and upholding it, and the inconveniences in operating it. That makes the risk evaluation subjective<\/em>, too: We may disagree over how risky we think a given threat is (and, separately, we may thus disagree over the protection costs worth incurring). You could spend an organization\u2019s entire operating budget on solving increasingly marginal threats; at some point, it\u2019s just not worth it anymore:<\/p>\n\n\n\n<\/p>\n\n\n\n
<\/p>\n\n\n\n
\n\u201cCybersecurity is all about tradeoffs. The goal is to pick the right level of protection so that nothing gets compromised, without the protection itself getting in the way or costing too much\u201d (page 53)<\/p>\n<\/blockquote>\n\n\n\n
<\/p>\n\n\n\n
In the more meaty chapters, filled with actionable lists and to-dos enough to take up several people\u2019s full-time occupations, he\u2019s definitely<\/em> overwhelming said newbies\u2026 \u201cDefending\u201d Bitcoin, the network (as well as your own private keys) isn\u2019t and can\u2019t reasonably be<\/em> a full-time commitment. For the sake of delivering a comprehensive treatment, it\u2019s admirable that the author includes all this, but it\u2019s also terrifying. All the ways in which I can go wrong\u2026<\/em>
<\/p>\n\n\n\nHyperbolic Contradictions Won’t Rug the Spammers<\/h2>\n\n\n\n
<\/p>\n\n\n\n
The arguments for either side of the broad schism running through Core-Knots, arbitrary data, mining (template) centralization, and node settings are presented competently and succinctly, only occasionally misleading. To de Wolf\u2019s credit, they\u2019re portrayed miles better<\/em> than the often performative mudslinging we\u2019re used to from Twitter or conference stages. This is the best possible version of the argument; whatever your stance on quantum, Bitcoin Core, Knots, or nonmonetary data on Bitcoin,<\/strong> Defending Bitcoin<\/em><\/strong> is the bright, shining star for considering these themes.<\/strong>
<\/p>\n\n\n\nDe Wolf definitely goes too far at times, and he\u2019s repeatedly too shilly for Knots and OCEAN.
<\/p>\n\n\n\n
<\/p>\n\n\n\n
He plays fast and loose with \u201cfungibility\u201d, implying that anything impinging on one UTXO\u2019s interchangeability with another undermines its use as money: \u201c[I]f \u2018clean\u2019 Bitcoin spends freely while \u2018tainted\u2019 Bitcoin gets stuck in limbo, it stops working as money<\/strong>\u201d (page 207). Gold and fiat, two rival monetary systems, have performed their monetary functions reasonably well, even with quite a lot<\/em> of obstacles to their global fungibility.
<\/p>\n\n\n\n<\/p>\n\n\n\n
It\u2019s true that Bitcoin\u2019s don\u2019t trust, verify<\/em> ethos is meaningfully different than \u201cevery other monetary system [where] someone else decides what\u2019s valid.\u201d But it\u2019s hyperbolic to conclude that unless<\/em> a user runs a node, \u201ceverything above it works from a lie\u201d (page 225). There\u2019s a sliding scale of trust, the ease with which you could<\/em> verify transactions and keys via other means and, in consequence, the vast number of unconnected, somewhat-trusted people around.
<\/p>\n\n\n\nDe Wolf\u2019s rundown of Ordinals, NFTs, and the OP_RETURN debacle happens in Chapter 11 (ironically, since some would consider these themes pretty bankrupt\u2026). He admits that these \u201cunwanted\u201d components of Bitcoin are impossible to stop: \u201cIt\u2019s always been possible to embed data on Bitcoin\u201d (page 250), that \u201cBitcoin\u2019s technical properties mean that anyone can embed arbitrary data through known means at any time\u201d (page 263), and that \u201cvoluntary filtering alone can\u2019t solve it\u201d (page 263). He nevertheless spends the entire chapter assembling all the reasons nonmonetary data on Bitcoin is bad (\u201can abuse of a monetary network\u201d, page 265), and recommends users running Knots to ever-so-marginally prevent these transactions relaying across the network: \u201cRelay filtering through Knots is a preventative control that stops spam from propagating through your node\u201d (page 265), and \u201cMining on a spam-filtering pool or with your own template is the surest way to keep non-financial data out of blocks\u201d (page 264).
<\/p>\n\n\n\n
The fact that these efforts are individually expensive and inconvenient, yet practically achieve nothing, should not detract from the noble fight against spam:\u00a0
<\/p>\n\n\n\n
\n\u201cIn cybersecurity, we don\u2019t stop putting up defenses just because an adversary is hard to stop. It may be impossible to completely stop arbitrary data on Bitcoin, but it\u2019s absolutely possible to slow it down, force it into more difficult or more expensive vectors, and generally to repudiate it as a legitimate use of Bitcoin\u201d (pages 262-63).<\/p>\n<\/blockquote>\n\n\n\n
<\/p>\n\n\n\n
<\/p>\n\n\n\n
De Wolf paints himself into a corner by admitting repeatedly that arbitrary data is impossible to stop, but that somehow it\u2019s still incredibly important that you \u2014 yes, you!<\/em> \u2014 do everything in your power to microscopically close this devastating hack.
In these more controversial chapters, he straddles the line between dispassionate analyst and activist with a cause. The calls to individual action, no matter how minuscule or impotent, are entirely detached from the careful balancing of costs and benefits from the early portions of the book. \u201c[D]on\u2019t let convenience override the integrity of the system you\u2019re protecting\u201d (page 254), he writes, forgetting that \u201cLow-impact things that don\u2019t matter much aren\u2019t worth considering\u201d (page 55).\u00a0
<\/p>\n\n\n\nIn critiquing Core changes, he writes that \u201cBitcoin isn\u2019t an engineering project with a single set of design goals\u201d (page 283) \u2014 a statement in stark contrast with the money-only, Bitcoin \u201cmaximalism\u201d thesis that runs through the book. The segments attacking \u201carbitrary data abuse\u201d as \u201cunauthorized non-process traffic flooding the Level 0 network\u201d (page 256) seem pretty clear on what Bitcoin is supposed to be and for whom it works.
<\/p>\n\n\n\n
Every sort of counterargument here relies on what Bitcoin intends<\/em>, what Satoshi meant for<\/em> Bitcoin to be, and what the ultimate purpose<\/em> of the network is. We can disagree about the answers to these questions, but the point is that they\u2019re subjective, ambiguous, and mostly unanswerable \u2014 meaning that arguments based on an interpretation of what Bitcoin is supposed to be<\/em> become just that: hypothetical, subjective conjectures.
<\/p>\n\n\n\nIn the name of countering spam\/inscriptions\/unwanted data, getting rid of consensus-valid transactions isn\u2019t worth it. I suspect de Wolf reluctantly understands that \u2014 which is why his recommendations boil down to tame, virtue-signaling individual-level actions. Feeling good, not doing (much?) good<\/em>.<\/p>\n\n\n\n\n\u201cWhether BIP 110 specifically is the right vehicle to address arbitrary data remains an open question. I\u2019m clear in my position that arbitrary data is not good for Bitcoin<\/strong>, but changing the consensus rules in a way that breaks existing functionality is a drastic step\u201d (page 293).<\/p>\n<\/blockquote>\n\n\n\nIn an altogether characteristic moderation, he relaxes his position with a look to chain splits \u2014 the nuclear<\/em> option making most drastic proposals to counter \u201cspam\u201d not worth it.\u00a0
<\/p>\n\n\n\n<\/p>\n\n\n\n
What annoys me the most is the presumption that arbitrary data is infinitely profitable<\/strong>, thus is (or will) crowd out bitcoin\u2019s monetary use \u2014 an existential plague rather than a mostly harmless phenomenon at the, uh, uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy\u2026<\/em>
<\/p>\n\n\n\n\n\u201cSpammers aren\u2019t using Bitcoin as money. Rather, they\u2019re using it as a way to generate value for themselves through the data they embed. It\u2019s worth it to them to pay the fee to get their data inscribed on Bitcoin, and presumably they expect to make their money back\u201d (page 260).<\/p>\n<\/blockquote>\n\n\n\n
<\/p>\n\n\n\n
Call me blue-eyed, I just don\u2019t believe there\u2019s a constant, ever-lasting demand for worthless digital junk. Besides, in manias and bubbles, that sort of leaning-against-the-wind never works \u2014 in part because people (irrationally) hoping to profit from peddling nonsense think they\u2019ll profit so much<\/em> that whatever tiny obstacles you place in their path are but a nuisance. The kicker is that they won\u2019t<\/em>; thus, the existence of a final sucker.
<\/p>\n\n\n\nThe security assessment that the book constitutes, complete with ratings and urgency, is terrifying but also probably long overdue for a leaderless monetary project. It\u2019s admirable that the author created a comprehensive, actionable guide for all the ways you can defend B(b)itcoin. But \u201cDefending\u201d Bitcoin, the network and your own stash, can\u2019t reasonably be a full-time job. What was supposed to be an exit from a part-time investment job outperforming inflation became, implicitly, a part-time technical job staying up to date in software maintenance, running a Lightning node, juggling multisig keys for self-custody assurance, running multiple node implementations, and constructing block templates from your solar-powered BitAxe.\u00a0
<\/p>\n\n\n\n
The final, optimistic takeaway is that this deep dive made de Wolf see Bitcoin as more resilient than he first supposed. Despite outlining dozens of threats, across AI and quantum and spammers and poor key management and colluding miners and faulty privacy and hostile governments, de Wolf\u2019s \u201cassertion is that Bitcoin has held up remarkably well\u201d (page 383). The downside is that we<\/em> are its security team.
<\/p>\n\n\n\n<\/p>\n\n\n\n
It\u2019s a beautiful summary of a painstaking journey, with lots left to do. The repeated emphasis on balancing convenience and security lingers.
<\/h2>\n\n\n\n
<\/p>\n\n\n\n
SELECTED QUOTES:<\/p>\n\n\n\n
\n- \u201cIn every system I\u2019ve ever worked on, the most common failure wasn\u2019t a sophisticated attack. It was a human mistake\u201d<\/strong> (pages 389-90).<\/li>\n\n\n\n
- \u201cIn 2017, Core had defended Bitcoin\u2019s monetary properties against outside pressure. In 2025, it was telling the community that disagreement would have to express itself somewhere else\u201d (pages 280-81).<\/li>\n\n\n\n
- \u201cQuantum threatens the cryptographic assumptions that protect keys and secure mining. AI threatens the human and economic layer around the protocol, from development and social engineering to mining economics\u201d (page 360).<\/li>\n\n\n\n
- \u201cThe protocol doesn\u2019t defend itself. People defend it through the choices they make about what software to run, what development to fund, and what behavior to tolerate\u201d (page 298).<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"
An exclusive review of Luke de Wolf’s new book “Defending Bitcoin,” as it ran in Bitcoin Magazine Print’s “Quantum Issue” last month. <\/p>","protected":false},"author":8,"featured_media":4881,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_price":"","_stock":"","_tribe_ticket_header":"","_tribe_default_ticket_provider":"","_tribe_ticket_capacity":"0","_ticket_start_date":"","_ticket_end_date":"","_tribe_ticket_show_description":"","_tribe_ticket_show_not_going":false,"_tribe_ticket_use_global_stock":"","_tribe_ticket_global_stock_level":"","_global_stock_mode":"","_global_stock_cap":"","_tribe_rsvp_for_event":"","_tribe_ticket_going_count":"","_tribe_ticket_not_going_count":"","_tribe_tickets_list":"[]","_tribe_ticket_has_attendee_info_fields":false,"_EventAllDay":false,"_EventTimezone":"","_EventStartDate":"","_EventEndDate":"","_EventStartDateUTC":"","_EventEndDateUTC":"","_EventShowMap":false,"_EventShowMapLink":false,"_EventURL":"","_EventCost":"","_EventCostDescription":"","_EventCurrencySymbol":"","_EventCurrencyCode":"","_EventCurrencyPosition":"","_EventDateTimeSeparator":"","_EventTimeRangeSeparator":"","_EventOrganizerID":[],"_EventVenueID":[],"_OrganizerEmail":"","_OrganizerPhone":"","_OrganizerWebsite":"","_VenueAddress":"","_VenueCity":"","_VenueCountry":"","_VenueProvince":"","_VenueState":"","_VenueZip":"","_VenuePhone":"","_VenueURL":"","_VenueStateProvince":"","_VenueLat":"","_VenueLng":"","_VenueShowMap":false,"_VenueShowMapLink":false,"footnotes":""},"categories":[73],"tags":[80,72,74],"class_list":["post-4879","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-books","tag-bitcoin","tag-bitcoiners","tag-defending-bitcoin"],"_links":{"self":[{"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/posts\/4879","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/users\/8"}],"replies":[{"embeddable":true,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/comments?post=4879"}],"version-history":[{"count":16,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/posts\/4879\/revisions"}],"predecessor-version":[{"id":4898,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/posts\/4879\/revisions\/4898"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/media\/4881"}],"wp:attachment":[{"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/media?parent=4879"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/categories?post=4879"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/btchel.com\/fi\/wp-json\/wp\/v2\/tags?post=4879"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"\"](\"https:\/\/btchel.com\/wp-content\/uploads\/2026\/10\/Books-Books-2-Luke-de-Wolf-edited-745x1024.jpg\")
<\/figure>\n\n\n\n