The Constitution of the United States of America has been called one of the hinges of history. For all its imperfections and the compromises over slavery it was a revolutionary document articulating the belief that sovereignty lies with those who are governed and not with those who govern.

The UK took a different path but arrived at a similar recognition of the location of sovereignty. Whilst there are written sources on process, eg Erskine May, there is, however, no definitive written statement of the British Constitution. It is a set of conventions and practices which politicians have more or less adhered to over time.

No one would argue that either constitutional model is perfect but perfection is not a yard stick with much use in the world of politics. Democratic politics is about satisficing, about how the clash of ideas and interests are resolved characteristically by compromise and a willingness to accept outcomes which you have opposed. It may not always get the best answer but will more often than not avoid the worst and critically provide for accountability by the governed of those that govern.

However, crucially, it can only function if there is an overall commitment to, acceptance of and and trust in, the system for securing governments and process of aggregating political ideas and interests. There needs to be an acceptance that the written or unwritten constitution provides a reliable, equable and fair skeleton holding the body politic together. Prime Ministers and Presidents may come and go and the style of governance may ebb and flow but the rules of the game sustain through time, creating continuity and trust in the process if not always happiness with every outcome.

In recent years, on both sides of the Atlantic, weaknesses in this model have come to light. Conventions and indeed laws are only as strong as the willingness of the political elite to follow them. Both here and in America politicians of all persuasions have been engaged in an escalating process of the weaponisation of their respective constitutional norms. This is a very dangerous path. It goes to the integrity of the skeleton without which trust in the process is undermined and commitment to compromise destroyed.

There is no doubt the process is more brazen and ubiquitous in the States, for the time being. President Trump has no understanding of the notion of the separation of powers, the role of an independent judiciary, a free press, the location of sovereignty, or in truth much at all. He is a uniquely awful individual who brings to everything he does a combination of ignorance and prejudice which when combined with the power of his office is truly frightening.

Whilst he has brought a terrible destructive force to the rejection of accepted ways of behaving in truth he is accelerating and deepening a process which has been in chain for some time. Furthermore, culpability for what is happening now is not confined to President Trump. Mitch McConnell, the Republican leader of the Senate has, with the backing of most of the rest of the GOP, sustained and supported his President in a manner which, if there is any justice, history will judge very harshly.

Back here in the UK it is the case that both sides in the Brexit debate have sailed close to the wind in terms of bending and stretching constitutional norms. However, the prorogation of Parliament for 5 weeks at a critical point in the Brexit process raises the the bar to a whole new level. It is a typical populist ploy to claim there needs to be progress and Parliamentarians are getting in the way of firm and clear government. It is also typical of despotic double speak that one claims to be bringing sovereignty back to Parliament by closing it.

If precedents are manipulated to do something they were not intended to they start to lose legitimacy. They then come to mean whatever the government of the day thinks they mean. This completely undermines their function of constraining political battles within civilised bounds. If the rules of the game don’t apply to one side they don’t apply to any. Political debate becomes ever more acrimonious. Effective government ceases, in the United States this has literally involved the shutdown of government 10 times in recent years. The spectacle of all this undermines the faith of the governed in the very process of democratic government and they seek assurance and stability elsewhere. And there is always someone willing to provide that stability, even if the assurance is short lived.

There is a complacency about the strength of democracy, which perhaps derives from the fact that most citizens in the US and UK have experienced nothing other. It may be this complacency has also infected our political elite. They feel they can manipulate the system and it will spring back. They can twist its arm tighter and tighter and it will never break. They need to be aware, however, that a broken convention will take a lot longer to repair than a broken arm, if it is repairable at all.

For a minority of Parliament Brexit is an idee fixe which must be achieved at all costs. They seem to have assessed the political, constitutional and economic cost they are risking as less than the benefits from a country free from Europe. If they get their way we must hope they are right, even if we are sure they are wrong, because if they are wrong they may have inflicted severe harm on democracy in the UK, which, given the current global context, may have implications around the world.