So, Nick Clegg has made his choice, David Cameron is Prime Minister, and Britain heads into the unfamiliar world of coalition government. Again, Disraeli’s famous line that “England does not love coalitions” will be put to the test.

For the Liberal Democrats, coalition comes with particularly bad precedents. The past three coalition governments in Britain were during the two World Wars and the Great Depression. The First World War coalition all but destroyed the Liberal Party; the National government during the Depression was the ruin of what was left of it, and the Second World War coalition was the last time that Liberals had any participation in government.

There has been one subsequent near-government experience: in 1977 the Liberals entered into an agreement to support the then-tottering Labour government in return for certain policy concessions, but without entering the ministry. The agreement only lasted a year, and in 1979 the Liberals voted with the Tories to bring down the government: at the subsequent election they lost a quarter of their votes and fell back to 11 seats.

Britain has a deeply held self-image as a two-party system. In reality, there have often been powerful third parties: the Canningites in the late 1820s, the Peelites in the 1850s, the Irish Nationalists from the 1870s onwards and the Liberal Unionists in the 1880s and ’90s. But actual coalitions tended to be short-lived and unsuccessful — such as the Peelite-Whig government of 1852, which fell apart during the Crimean War.

The 20th century experience was no different. In 1914, the Liberals were in government; not travelling well, but unquestionably one of the two major parties. But the war was a disaster for a party based on free trade and international co-operation. The Conservatives, with no scruples about aggressive war making, soon came to dominate the wartime coalition; the Liberals split, and when the Conservatives ejected the remnant from the coalition after the war, they found the Labour Party had supplanted them as the main force on the left.

In 1924 and 1929 the Liberals supported minority Labour governments, but without getting anything in return. This display of impotence hurt them electorally, particularly since Labour was willing to suffer short-term losses in order to squeeze out the Liberals and supplant them. But the Liberals still resisted any co-operation with the Tories; as the Liberal Magazine put it in 1923:

“… there are no conceivable circumstances in which the Liberal Party could enter into a coalition, alliance, partnership, understanding, or other collusive arrangement … with the Conservative Party. Liberals are not separated from Conservatives merely by a difference in the way of doing things … They are separated in their fundamental aims, in thought, in idea, in principle …”

As the Greens in Australia risk discovering, a minor party that can only deal with one side has trouble maintaining a raison d’etre. The Liberals did ultimately link up with the Conservatives in the National government of 1931, but they soon split again before being all but wiped out in the 1935 election.

After 50 years in the wilderness, the Liberals returned to relevance in the 1980s, and now Nick Clegg has led them back to the government benches. As the only combination that could provide stable government, the agreement with the Tories makes considerable sense. But the sad history of coalition politics is bound to give him some sleepless nights.