During John Bolton’s recently ended tenure as national security adviser, he convinced President Trump that the Venezuelan leader Nicolás Maduro was on the verge of losing power. Mr. Bolton is reported to have been the architect of the several failed attempts to unseat President Maduro, a frequent target of Mr. Trump’s bluster.

We now know that Mr. Maduro’s fall was not imminent. Instead, Mr. Bolton bluffed on the high-ranking military officials who were about to betray Mr. Maduro; he bluffed on the number of people who would take to the streets in April to try to overthrow the Maduro regime; and he also seemed to believe that sanctions would work very quickly. Most important, though, his biggest mistake was to proceed along those lines without any Plan B in case this Plan A did not work. In the end, he has succeeded only in making Mr. Maduro stronger.

The best proof of this foreign policy debacle is that last week, for the first time since January, Mr. Maduro traveled abroad, choosing Moscow, logically enough, as his destination. He also achieved his first diplomatic victory in years last week at the United Nations Human Rights Council in Geneva, persuading enough countries, including China, Cuba, Egypt, Iran and Mexico, to vote for a resolution t o promote a peaceful solution to the Venezuelan crisis without foreign interference, which should be taken with a grain of salt coming from Mr. Maduro. He was, however, forced to accept the creation of a fact-finding mission to investigate the most egregious human rights abuses in Venezuela. This setback will come back to haunt him.

Mr. Maduro also pulled out of talks with the opposition in Barbados without serious consequences, another sign of his resilience. Washington’s lack of a Plan B has allowed the Venezuelan dictator to outlast his foreign and domestic opponents. This is almost reminiscent of the Bay of Pigs.