This morning, the headlines confirmed what had been rumoured for weeks: that a Prime Minister who has never faced a general election, and who can no longer be sure of a majority in the House of Commons, plans to override opposition to his policy agenda by suspending our democratic institutions. It means that the crisis gripping British politics is no longer fundamentally about Brexit. It is about the future of our parliamentary democracy.

In a democracy, the right to govern must always flow from the public. The UK does not have a presidential system. Its only democratic institution is the House of Commons, and the right to form a government comes solely from the support of a majority of MPs. By asking the Queen to suspend parliament for five weeks, Boris Johnson has tacitly accepted that he no longer has that support. To carry on regardless – and to push through a fundamental policy change that he knows would be voted down – would shatter the most basic principles of parliamentary government.

This cuts to the heart of Johnson’s democratic mandate – indeed, of his right to the premiership itself. Take away his parliamentary support, and all that is left are the votes of 92,153 unelected Tory members. A mature democracy cannot allow party activists to override parliament or to usurp the democratic functions of MPs.

We will be told, of course, that it is parliament that is frustrating democracy; that Johnson’s mandate comes from the 17.4 million Leave votes in the 2016 EU referendum. But that referendum said nothing about the terms of Brexit. Johnson himself voted twice against Theresa May's Withdrawal Agreement, which would have seen Britain leave the EU at the end of March. Presumably he did so because he thought the terms were unacceptable – and that the referendum did not mandate Brexit under all possible conditions. If Johnson had the democratic right to reject May’s proposals, MPs must equally have the right to block his.

So how do we decide what those terms should be? Two main options lie ahead. We can do this democratically – whether through our elected representatives, or through a further referendum – or we can do it autocratically, by suspending parliament and adopting whatever policy the Prime Minister sees fit. What we cannot do is to pretend that suspending parliament is democratic: that a single heroic leader can embody in his own person “the will of the people”, or use that as a weapon to crush dissent from elected representatives. That leads down a much darker path.

Parliamentary government is often frustrating. It brings together a cacophonous array of competing voices, with as many different opinions as there are citizens. It can be ponderous, verbose and slow to reach agreement. Yet such is the nature of a democratic society. In a complex, pluralistic state, the “will of the people” is not a single intelligence, issuing instructions to parliament; it is a negotiation between different voices and interests, who come together in our democratic institutions to “parley”.

Johnson is not the first to find this irksome. In the 1930s, as leader of the British Union of Fascists, Oswald Mosley struck out against “the false liberty of a few old men to talk for ever in the present parliamentary system”. He dreamed of a “government armed by the people with complete power of action”; dependent not on “the intrigues and manoeuvres of conflicting parties, but on the will of the nation directly expressed”. Britain rejected that road in the 1930s. It should do so again today.

Most MPs do not sign up for their job expecting to face a constitutional crisis, or a choice between their Prime Minister and the principles of a parliamentary democracy. But that is the historic decision they now face; particularly those on the Conservative benches. Do they believe in the principles of parliamentary government? If they do, what price are they prepared to pay?

We must hope that they think carefully, and choose wisely.