The rapidly escalating crisis in Venezuela reminds the world of the difference a new American administration can make. Feature how fast President Trump recognized the new president of the oil-rich wreck of a socialist country. As protests swelled over a stolen election, a reform president arose to replace Nicolás Maduro. Whammo. The Trump administration swung in with prompt diplomatic recognition.

What a contrast with, say, President Obama’s lackluster, appeasement-oriented reaction to the Green Revolution in Iran. That broke out at June 2009, after allies of President Ahmadinejad hijacked the election that year. Hundreds of thousands of Iranians took to the streets, desperate for American support for Iranian democracy. They were crushed by the regime, as Mr. Obama headed for hills.

We like the way our erstwhile diplomatic leg, Eli Lake, summed it up in a retrospective column a few years back. “Obama publicly downplayed the prospect of real change at first, saying the candidates whom hundreds of thousands of Iranians were risking their lives to support did not represent fundamental change. When he finally did speak out, he couldn’t bring himself to say the election was stolen.”

Soon he was using airplanes to ship the Ayatollahs pallets of cash. That doesn’t seem likely in the case of Mr. Trump and the Venezuelans. After Mr. Trump recognized the presidency of the 35-year-old National Assembly leader, Juan Guaidó, Mr. Maduro ordered the expulsion of American diplomats in Venezuela within 72 hours. Mr. Trump promptly made clear that we’d ignore the deadline.

Our man at the United Nations, Benny Avni, thinks the contrast between Messrs. Obama and Trump augers well in the current crisis, and is one of its salient features. He’s not a supporter of everything President Trump does, by any means, but in respect of Venezuela, Mr. Avni says, the President has been “very tough, right from the start” and has done “exactly the right thing.”

Mr. Avni, by the way, credits not only President Trump and the state secretary, Mike Pompeo, but also the National Security Adviser, John Bolton, and Senator Marco Rubio. Mr. Avni marks the malign role of Cuba, which keeps the Maduro government in power. Mr. Avni says the next thing to watch for is action at the U.N., where it looks like the Security Council will meet on Venezuela Saturday.

Once the United Nations gets involved, the whole situation could end up in a cocked hat (Russia, a Maduro ally, has a veto at the Security Council). Things are less likely, though, to go awry when an American administration is taking a strong stand. There are some extremists even in our Congress, such as Democrats Ilhan Omar, Alexandria Ocasio-Cortez, and Tulsi Gabbard, who are taking a sympathetic line toward the Maduro regime.

Even the New York Times, though, is acknowledging that Mr. Maduro is beyond his sell-by date and that Senor Guaidó deserves support. So is the Speaker, Nancy Pelosi. Which leads to an intriguing thought. Wouldn’t it be something were we to find, amid all the sturm and drang in Washington, a crisis in which American politics really do stop at the water’s edge?