The consensus-driven bitcoin community has been polarized in recent months by the Segwit2x hard fork. The New York Agreement timed this fork to roll out in mid-November, but on November 8th, the split was called off in a post by several of the movement’s leading stakeholders.

The intensity of the ideological debate has created noise and confusion surrounding the fork’s broader context. We’ve tried to explain the journey to the fork, and its eventual termination, in this analogy:

The Bitcoin Express

Everyone is on the train. A group of hardcore train travellers are gathered in the Marriott cafe car working on their laptops and discussing their impending destination. They make an agreement that it would be better for the train to go somewhere else. They call this the Train Agreement.

They are approaching a split (fork) in the track ahead.

To make it to this new destination, they must pull a nearby lever, which would disconnect the back of the train from the rest at the upcoming split. This will allow them to continue on a new path, to their preferred destination.

They think that most of the people on the train would also like to change destinations. But the the train is very long and they can only interact with the people in the neighboring cars. They are also unsure whether the engine is at the front of the train or at the back. There may even be one at both ends.

If the engine is at the back of the train, then they could successfully disconnect from the rest of the train and make it to their new destination. If the engine is at the front of the train, disconnecting from the head of the train would leave them stranded. Their only chance of making it to any destination comes from remaining connected with the entire train. And what if there are two engines, and neither end could make it to their respective destinations without both engines running simultaneously? Pulling the lever will surely hurt everyone involved. No one would get to their destination. Other train companies or even buses would have to be used for transportation going forward.

And what do the rest of the passengers in the back of the train think? What about those in the front of the train? If the passengers in the back of the train do not support this change in destination, will they pull another lever at the next fork in the road, stranding their cafe car without an engine, in the middle of nowhere? Without more consensus, clarity, and understanding of their situation, is it worth the risk?

Without answers to these questions, they do not pull the lever. And neither did those leading the Segwit2x fork.

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