Perhaps not in the strict legal way[1], but if you say "I'm going to do X" as a government then you kind of have an obligation to actually do X unless there's a

Perhaps not in the strict legal way[1], but if you say "I'm going to do X" as a government then you kind of have an obligation to actually do X unless there's a really good reason not so, because people's livelihoods depend on it. This includes actions taken by a previous government: generally successive governments fulfil the obligations of the previous ones, even those it disagrees with. That's the only way you can run a reasonable long-term stable and reliable government. Of course a new government can change things, but this is often a long process which also includes meeting previous obligations. [1]: Or maybe it does, I don't know. I wouldn't assume anything from the person trying to abolish citizenship birthright in a way that's clearly and obviously unconstitutional.