为什么两阶段提交被认为是原子的？

Two phase commit is described as an "atomic commitment protocol". I would expect this to mean that all clients see the state of the world from either before a transaction commits, or after it commits -- with no in-between state. It seems though that it can enter a state where a transaction is partially committed and clients see inconsistent data, breaking atomicity.Two phase commit is described as an "atomic com