The only thing that bothers me more than Mitt Romney’s falsehoods is when Romney repeats the falsehoods after they’ve been proven untrue.

In last night’s debate, the former governor, who’s routinely struggled with the basics of military and national security policy, complained, “[W]e keep on shrinking our Navy. Our Navy is now smaller than any time since 1917.”

Romney backer John Bolton raised the same concern in a Wall Street Journal op-ed: “The Navy has only 285 ships today, the fewest since World War I, and it is straining to uphold its unique global responsibilities.”

The problem isn’t with the data, per se, but with the metric. Romney and his campaign want to give the public the impression that the Obama administration is somehow scaling back the military, leaving us vulnerable. But as multiple fact-checks have made clear since the Republican campaign starting pushing this line, the claim is wildly misleading.

[E]ven by that standard, Obama’s Navy has more ships than at any point in the last four years of the Bush administration. The Navy’s downsized fleet was a result of a decades-long reorganization rather than any Obama administration policy. More to the point, we’re getting a lot more bang for our buck — we’ve swapped dreadnoughts, monitors, and 50-gun frigates for air-craft carriers and nuclear submarines. Which would you want in a fight?

And this once again leaves us with one of two options. Romney is either (1) confused about military policy, and didn’t do his homework before popping off on a subject he doesn’t understand; or (2) trying to deliberately fool voters, and counting on the media not to call him on it.

It’s an either/or dynamic that comes up all the time with this guy.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.