📚 The Blocksize War by Jonathan Bier
Book Club - Book #1
Jonathan Bier’s The Blocksize War is an essential read for anyone who wants to understand one of the most pivotal battles in Bitcoin’s history. Covering the period from 2015 to 2017, the book provides a detailed, behind-the-scenes look at Bitcoin’s Civil war over the block size limit, a battle that ultimately shaped the future of Bitcoin and the broader cryptocurrency ecosystem.
This is more than just a technical debate—it’s a story of power struggles, corporate interference, and a grassroots movement that proved Bitcoin is truly controlled by its users, not miners or big businesses.
The Premise: Why Did the Blocksize War Happen?
As Bitcoin adoption grew, so did transaction volume, leading to congestion and higher fees. A faction of developers, miners, and corporations—later known as the Big Blockers—argued that increasing Bitcoin’s 1MB block size would allow more transactions per second, making Bitcoin more usable for daily payments.
Opposing them were the Small Blockers, who believed that larger blocks would lead to centralization, as only large-scale operations could afford the storage and bandwidth needed to run full nodes. They insisted that Bitcoin should scale through Layer 2 solutions rather than altering the core protocol.
This fundamental disagreement escalated into a multi-year battle involving software forks, political maneuvering, and a showdown between corporate interests and grassroots Bitcoiners.
Key Events Covered in the Book
Bier meticulously documents the key moments of the war, giving readers a clear timeline of how the conflict unfolded:
Early Proposals (Bitcoin XT, Classic, Unlimited) – Various attempts to increase the block size failed due to lack of community consensus.
SegWit & the User Activated Soft Fork (UASF) – In 2017, Bitcoin developers introduced Segregated Witness (SegWit) to improve transaction efficiency. When large miners refused to support it, the Bitcoin community initiated the UASF, forcing SegWit’s activation and proving that users—not miners—govern Bitcoin.
The New York Agreement & SegWit2x – Big businesses (Coinbase, Bitmain, Digital Currency Group) negotiated an agreement behind closed doors to increase Bitcoin’s block size to 2MB, but their plan collapsed when the wider Bitcoin community rejected it.
The Bitcoin Cash Fork – After losing the war, Big Blockers split off and created Bitcoin Cash (BCH) with an 8MB block size. Over time, BCH has lost relevance, proving that bigger blocks were not the solution.
The Bitcoin Trilemma: The Core Issue Behind the War
The Blockchain Trilemma, states that a blockchain can only optimize two out of three of the following:
Decentralization – Anyone can verify transactions and participate in the network.
Security – The system resists censorship and attacks.
Scalability – The network can handle a high volume of transactions.
Bitcoin chose decentralization and security over scalability, ensuring that anyone could run a full node and verify transactions without relying on centralized entities.
Other projects that tried to "fix Bitcoin" by prioritizing scalability have all failed in some way:
Ethereum (Proof-of-Stake) has led to validator centralization.
Solana and Avalanche (High-Speed Chains) require expensive hardware, limiting participation.
Bitcoin Cash (Big Blocks) weakened decentralization and security while failing to gain adoption.
Bitcoin’s Scaling Solution: Layers, Not Bigger Blocks
Rather than compromise on decentralization, Bitcoin’s solution was layered scaling:
SegWit made transactions more efficient.
The Lightning Network allows for instant, low-cost transactions off-chain.
Sidechains and Layer 2 solutions continue to expand Bitcoin’s capabilities without altering its core security model.
This layered approach mirrors how the internet scaled—not by increasing bandwidth infinitely, but by adding protocols like HTTP, TLS, and CDNs on top of the base layer.
Final Verdict: A Must-Read!
The Blocksize War is an essential book for anyone who wants to understand why Bitcoin remains the most decentralized, censorship-resistant cryptocurrency and why there is no second best. The book is more than just a history lesson; it’s a case study in governance, decentralization, and why Bitcoin has remained resilient where other cryptocurrencies have and will falter. Bier provides a gripping account of how Bitcoin nearly fell into corporate control—and how the community fought back and won.
You can buy the book here:
Disclaimer: The content in this newsletter is for informational purposes only and should not be considered financial, investment, or legal advice. Being sovereign involves risks, don't trust, verify! AKA, do your own research and use this information at your own risk.
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