President Obama is getting widely mocked by commentators and Republicans for using the phrase “permission structure” at his presser yesterday in the course of claiming that Republican officials are constrained from cooperating with him because their base would see it as a “betrayal.”

So it’s good to have a Republican Senator on record confirming that Obama is right about this.

I’m talking about Pat Toomey. The Senator from Pennsylvania didn’t directly address Obama’s remarks, but something he said in another context perfectly confirms the President’s diagnosis of the GOP.

Via Amanda Terkel, Toomey admitted in an interview that expanded background checks went down to defeat because Republicans opposed the bill out of a desire to deny the president a victory. Here’s what Toomey said, according to a write-up in the Times Herald:

“In the end it didn’t pass because we’re so politicized. There were some on my side who did not want to be seen helping the president do something he wanted to get done, just because the president wanted to do it,” Toomey said.

That’s pretty significant. But Toomey’s subsequent effort to walk this back is in some ways even more so:

In subsequent comments, he tried to walk that remark part-way back by noting he meant to say Republicans across the nation in general, not just those in the Senate. “The toughest thing to do in politics is to do the right thing when your supporters think the right thing is something else,” Toomey said.

According to Toomey, what doomed Manchin-Toomey is that Repulicans across the country opposed it only because the president supported it.

Having a Republican on record confirming this is useful. As Steve Benen notes, it makes all the suggestions that Obama needs to “lead” and “twist arms” look pretty silly. Indeed, Toomey’s concession is particularly relevant to the ongoing debate over Obama’s remarks at his presser yesterday. Here’s the bit that has all of the Green Lanternites out there slapping their knees and laughing uproariously:

“I cannot force Republicans to embrace those common-sense solutions…It’s tough. Their base thinks that compromise with me is somehow a betrayal. They’re worried about primaries. And I understand all that. And we’re going to try to do everything we can to create a permission structure for them to be able to do what’s going to be best for the country. But it’s going to take some time.”

But is this materially different from what Toomey said about his own party? No, it isn’t.

Toomey is in a good position to address this, too. He took a very big political risk by entering into negotiations on a proposal to expand background checks that he knew would rile up the “gun rights” portion of the GOP base. Toomey and Joe Manchin — both Senators from states with deep gun cultures – negotiated a compromise that went to great lengths to show deference to gun culture and gun owners. It exempted private transfers through non-commercial portals, so transfers among family members, friends, gun hobbyists and hunters would be untouched, and strengthened prohibitions against the national gun registry conservatives claimed to fear. The idea underlying the proposal was backed by over eight in 10 Americans. It had the support of a majority of the Senate — including Republicans like John McCain.

Toomey spent weeks trying to talk fellow Republicans — officials and voters alike — into accepting this compromise. It didn’t work — virtually all Republican Senators said No. And there’s no mystery as to why. By Toomey’s own telling, Republican voters across the country wouldn’t support this common sense effort to address a problem that’s killing thousands of Americans per year, simply because Obama supported it.

Obama’s use of the odd phrase “permission structure” is not the real problem here.

Greg Sargent writes The Plum Line blog, a reported opinion blog with a liberal slant -- what you might call “opinionated reporting” from the left.