There was a Blocksize War in 2016-2017 that tested how decentralized Bitcoin really was. One faction of the Bitcoin community, the Big Blockers, wanted to increase the maximum size of each block, from 1 megabyte to something higher like 32 megabytes. This increase would allow many more transactions to fit in each block, which means much higher transaction throughput for the Bitcoin blockchain. This would help scale Bitcoin to handle more users and payments. Major companies such as exchanges and miners wanted this change as it would be good for their businesses.

However, a second-order effect of increasing block size is that fewer individuals would be able to run full nodes when storage and bandwidth requirements go up 32 times. Control over the network would then centralize to the companies that can afford massive servers and make it more likely that other rules will change in the future. So the full node operators, many of whom were using cheap desktop computers, defeated the big companies and prevented the block size increase.

In response, the Big Blockers hardforked Bitcoin at the end of 2017 to create a new blockchain and token, called Bitcoin Cash, which had 32 megabytes per block. At the time of the hardfork, everyone who owned Bitcoin also owned the same number of Bitcoin Cash, and then the two blockchains diverged. Since then, Bitcoin Cash has lost over 95% of its market value and mining hashpower compared to Bitcoin, showing the importance of using a bigger and more secure network. As of July 2024, the Bitcoin blockchain is just over 500 gigabytes, which means individuals can still easily run a full node with an affordable computer.