Over Memorial Day weekend, an American political party held a contested convention and the roof did not fall in. There were no riots and no thrown chairs, and the Libertarian Party nominated a pair of former two-term Republican governors—Gary Johnson of New Mexico and Bill Weld of Massachusetts—for president and vice president. While the Republicans seek to ensure a smooth, debate-free national convention by rallying around a man who has never held political office, a so-called fringe party has chosen experience over novelty.

It took two ballots for Mr. Johnson to secure the nomination over several rivals with no governing experience. Some Libertarians questioned his commitment to making government as small as possible; he got some boos for saying he would have signed the Civil Rights Act of 1964. Mr. Weld faced tougher scrutiny, partly for his support for gun-control laws when he was governor of Massachusetts. This is not surprising at a gathering where many feel it is oppressive for the government to require driver’s licenses.

The party’s slogan, “Minimum Government, Maximum Freedom,” is simplistic, but perhaps no more so than the idea that a wall across our southern border will make America great again. It is too early to say whether the Libertarians deserve to be included in this fall’s presidential and vice-presidential debates, but it is encouraging that the party has chosen two qualified, even-tempered candidates and is making an attempt to appeal to voters beyond its narrow base. The two major parties deserve the competition.