Parliament has the power to remove the Prime Minister, and it's possible that they would have done so if the Prime Minister failed to come to the aid of a histo

Parliament has the power to remove the Prime Minister, and it's possible that they would have done so if the Prime Minister failed to come to the aid of a historic ally. PM's have had no-confidence votes, or been pushed out of office before one would occur, over lesser issues. That aside, Parliament doesn't have to authorize via binding vote on these matters. They get a debate opportunity by normative convention, but any vote they took to override would not be binding unless they were willing to remove the PM. Nonetheless I think it's fair to place a sizeable portion of the blame on Parliament: They can't decide to go to war, but they do have some levers of power that would stop it, if they were willing to remove their PM. I certainly don't know where I put % blame here, but I'm equally sure Parliament was checking complicit on the issue.