Donald Trump’s preoccupation with Barack Obama may not be new, but it does seem to be intensifying. Did you happen to catch the Republican’s comments on Friday afternoon, at a White House foreign-policy event?

“All [congressional Democrats] want to do is impede. They want to investigate. They want to go fishing. And I watch Bob Mueller, and they have nothing. There’s no collusion, there’s no obstruction. They have nothing. It’s a disgrace. “We want to find out what happened with the last Democrat president. Let’s look into Obama the way they’ve looked at me. From day one, they’ve looked into everything that we’ve done. They could look into the book deal that President Obama made. Let’s subpoena all of his records.”

Trump proceeded to blame Obama for the air-conditioning system in the Oval Office.

I’m not sure which complaint was weirder, but it’s probably worth pausing to consider the curious calls for an investigation into Obama’s “book deal.”

In context, no one asked Trump to reflect on the Obama era or his predecessor’s book contract. Rather, the sitting president was asked about the investigations into his own scandals.

And that apparently triggered a reflex: Trump is infuriated by scrutiny, so he automatically called for comparable scrutiny of Obama. In his mind, the two men deserve equal examination of their respective records.

There are, however, a couple of obvious problems.

1. Congressional Republicans spent years desperately searching for a legitimate Obama scandal, but they couldn’t find one. In contrast, Trump is at the center of credible allegations of multiple felonies.

2. Trump scrambled on the spot to think of something controversial about Obama that might be worthy of an investigation, and the best he could do on short notice was pointing to the Democrat getting a book deal. Why would that be worthy of subpoenas and scrutiny? Trump didn’t say – because there was nothing to say.

I can appreciate the larger circumstances. Obama was a successful and popular president, whose stature continues to grow, while Trump struggles to understand his failures and low public support. It must be frustrating for the Republican, and it leads him to periodically take pointless rhetorical shots at his predecessor, hopeful that it might make Obama look worse and Trump look better.

He’s obviously mistaken.