Quote Originally Posted by Montmorency View Post
This scenario is a bad comparison, because it's basically impossible in our system of government. I don't mean just that those kinds of majorities are almost unattainable to either party (Obama had better in 2009), but that the institutions are arranged too differently from the UK's. The Constitution is not just a body of laws and norms here but a concrete and heavily contested document of a few thousand words. Functionally, only the states and courts - in practice just the courts - have "control" over the Constitution. The only way around this for a legislature (Congress) is to attempt to exercise jurisdiction stripping or to create new judicial positions to install hundreds of party hacks very rapidly in a way that has never occurred before, but this too does not make sense within your scenario because a legislative caucus and president with such intractable and vicious unity of purpose and will to power would never fail to pursue their substantive policy goals, be they extending healthcare access and reducing university costs or eliminating Medicare and public education.
Brexit doesn't contravene the UK constitution though, other than requiring the UK government to abide by domestic and international laws and agreements (which should be a given). Its implementation, however bad an idea it is (eg. hastily concluding a trade deal with Australia that's actually worse than the one we already had, and described as such by the Australian side), is just a collection of lawmaking. The UK government has a majority of lawmakers in the proportions that I translated above. In any case, the UK government has found time to contravene the constitution in numerous ways, but still claims that its lawmaking ability to enact Brexit is in danger.

If the US government has control of the executive, a 59 majority in Congress and a 12 majority in the Senate, would you expect it to carry out its manifesto? If it doesn't enact its manifesto, would you conclude that it cannot, or that it doesn't bother to? Especially if it finds time to amend the constitution in ways not listed in the manifesto.