There are many things we should remember about the events of late August and early September 2005, and the political fallout shouldn’t be near the top of the list. Still, the disaster in New Orleans did the Bush administration a great deal of damage — and conservatives have never stopped trying to take their revenge. Every time something has gone wrong on President Obama’s watch, critics have been quick to declare the event “Obama’s Katrina.” How many Katrinas has Mr. Obama had so far? By one count, 23.

Somehow, however, these putative Katrinas never end up having the political impact of the lethal debacle that unfolded a decade ago. Partly that’s because many of the alleged disasters weren’t disasters after all. For example, the teething problems of Healthcare.gov were embarrassing, but they were eventually resolved — without anyone dying in the process — and at this point Obamacare looks like a huge success.

Beyond that, Katrina was special in political terms because it revealed such a huge gap between image and reality. Ever since 9/11, former President George W. Bush had been posing as a strong, effective leader keeping America safe. He wasn’t. But as long as he was talking tough about terrorists, it was hard for the public to see what a lousy job he was doing. It took a domestic disaster, which made his administration’s cronyism and incompetence obvious to anyone with a TV set, to burst his bubble.

What we should have learned from Katrina, in other words, was that political poseurs with nothing much to offer besides bluster can nonetheless fool many people into believing that they’re strong leaders. And that’s a lesson we’re learning all over again as the 2016 presidential race unfolds.