Add this to the list of ways in which Donald Trump is conducting an unconventional presidency. For the first time in memory, Republicans just won a public debate over shutting down the government. Recent history says that the GOP can now expect a series of other wins this year on spending and debt.

On Friday, Senate Minority Leader Chuck Schumer (D., N.Y.) led most of his Democratic colleagues in denying the federal government the funding it needs to conduct normal operations. To end the shutdown, Democrats demanded that...