CAMBRIDGE, England — T he British do not normally have constitutional crises.

One reason is that we do not have a constitution, at least not in the normal sense. There is no single text labeled “The United Kingdom Constitution.” Instead, there is an accretion of statutes, conventions and customs — going back to Magna Carta of 1215 — which can be changed fairly easily. So we do not have the regular standoffs between executive and legislature which the United States seems to take in stride, even when (to British astonishment) it means closing down the federal government. The present conflict between Prime Minister Boris Johnson and a heterogenous majority in Parliament is new to us, exciting, even alarming.

The simplest explanation for the crisis is that it is the unforeseen consequence of our most recent constitutional change: the Fixed-Term Parliaments Act, passed in 2011, which brought our system closer to the American one. Before that, a prime minister who lost control of the House of Commons could call a new general election, and so end the standoff. The Fixed-Term Parliament Act stopped that; a parliamentary term is now supposed to last for five years. To shorten it requires two-thirds of legislators to vote for a new election. And so Mr. Johnson’s government is trapped: in office, but unable to carry out its policy. A general election would be the way of resolving this. The problem for the opposition is that Mr. Johnson would probably win it. So he wants an election, and they don’t.

But there are deeper explanations too. One of these — again on a constitutional level — is the conflict between representative democracy and direct democracy. On one hand, the will of Parliament; on the other, the will of the people, as expressed in the 2016 referendum on European Union membership. Most politicians (along with some members of the media, Europe-centered business interests and mainly metropolitan voters) wanted to stay. A majority of the electorate voted to leave.

We have had a string of referendums over the last 45 years, the most important being on whether to stay in the European Common Market in 1975 and on whether Scotland should remain part of the United Kingdom in 2014. The introduction of referendums into a parliamentary system was always, in theory, a source of potential conflict. But until now it had never become one, for the simple reason that every referendum vote until 2016 went the way that most of the political class wanted. The Brexit referendum was the first time that the majority of the electorate tried to impose its will on the elite. The elite was and still is horrified.