As much as Donald Trump loves baseless conspiracy theories, the president seems to have a special affinity for conspiracy theories involving his immediate predecessor in the White House.

On Tuesday, for example, Trump declared via Twitter, “Just out that the Obama Administration granted citizenship, during the terrible Iran Deal negotiation, to 2,500 Iranians - including to government officials. How big (and bad) is that?”

In reality, it’s neither “big” nor “bad.” It’s just nonsense. A Washington Post analysis explained:

This claim from Trump appears to have originated with a hard-line Iranian cleric who opposes the Iran deal. [Iranian cleric Mojtaba Zonnour] gave an interview to an Iranian newspaper, which was then repackaged by Iran’s semiofficial news agency, which was then picked up by U.S. media and then by the president on his Twitter feed (with some of the details garbled). Three senior Obama administration officials pushed back on Trump’s claim, including [Ben] Rhodes, who was intimately involved in the JCPOA negotiations.

The White House has produced literally no evidence to substantiate the president’s claim, and as the New York Times added, actual evidence points in the opposite direction: “American government data show no spike in naturalizations of Iranians or huge increase in green cards given to Iranians in 2015 when compared to the two previous years.”

All of which brings us to a place we’ve been many times: watching Trump peddle obvious falsehoods in the hopes of undermining Barack Obama.

But in this case, it’s also worth questioning how the Republican president came to believe this specific bogus claim.

Despite the fact that the United States generally has no use for propaganda from Iranian hardliners, Iranian cleric Mojtaba Zonnour’s literally unbelievable rhetoric was picked up by Fox News.

The report from the network noted that there’s no evidence to support the claims. but Donald Trump – who oversees and has access to a vast intelligence network – nevertheless decided to tell the American public that the Iranian hardliners are correct, going even further than Fox News was willing to go.

It would’ve been very easy for the president to make some cursory effort to determine whether he should believe nonsense from a radical Iranian cleric. Trump couldn’t be bothered – because he just didn’t much care whether the claims were true or not.

Last summer, the president declared, “When I make a statement, I like to be correct. I want the facts… Before I make a statement, I need the facts.” White House Press Secretary Sarah Huckabee Sanders later added that Trump “believes in making sure that information is accurate before pushing it out as fact.”

It’d be funny if it weren’t so sad.