Following Tennessee Senator Bob Corker’s announcement that he would not run for reelection next year, President Donald Trump—who had, once upon a time, considered Corker a potential secretary of state, attacked Corker, as his is wont, on Twitter, sneering:

Senator Bob Corker “begged” me to endorse him for re-election in Tennessee. I said “NO” and he dropped out (said he could not win without….my endorsement). He also wanted to be Secretary of State, I said “NO THANKS.”

Corker responded in kind, remarking, “It’s a shame the White House has become an adult day care center. Someone obviously missed their shift this morning.”

Interviewed by The New York Times hours after Trump’s Twitter meltdown, Corker accused Trump of treating the presidency like “a reality show…like he’s doing ‘The Apprentice’ or something.” Trump’s behavior should, said Corker, “concern anyone who cares about our nation.”

Will Corker channel his frustration with the president to good use, perhaps becoming a vocal opponent to the US-abetted slaughter in Yemen and emerging as a kind of heir to J. William Fulbright, who led the fight against Vietnam in the Senate? Unlikely.

Though he was heralded (by some) for his refreshing honesty about our increasingly unhinged president, it would be a mistake to gloss over Corker’s record, which (with the notable exception of his opposition to the Obama administration’s disastrous Libya intervention in 2011) has been consistently hawkish.

In the first place, Corker tried to downplay Trump’s obvious inexperience and volatility during the 2016 campaign. Corker told a reporter from The Tennessean, “I’m seeing from where I sit an evolution towards a more serious tone, towards addressing issues in a more full way.” “And I don’t,” continued Corker, “really worry about that caricature” of Trump, because “once you come into the Oval Office and you understand the tremendous decisions that you have to make…I think that there’s a tremendous soberness and typically when you go in, you end up with lots of very highly qualified people around you. Again, that just doesn’t bother me.”

And then there is Corker’s record as chairman of the Senate Foreign Relations Committee.

In his nearly three years as chairman, Corker has repeatedly endorsed the most hard-line positions, calling for greater US intervention (in Syria, in Ukraine, in Libya, in Yemen), while energetically trying to undermine President Obama’s signature foreign-policy achievement, the Joint Comprehensive Plan of Action, the Iran nuclear deal.

In 2015, during hearings on whether to approve the Iranian nuclear agreement, Corker accused then–Secretary of State John Kerry of being “fleeced” by the Iranians. He voted against the deal in 2015, and today is leading the effort (along with Arkansas Senator Tom Cotton) to undermine it, easing the way for the administration to reapply sanctions on Iran should it continue to carry out its ballistic-missile program (a program that was not subject to the terms of the original JCPOA).

Corker has also been a leading proponent for arming both the so-called “moderate” Syrian rebels as well as for sending lethal weapons to non-NATO member Ukraine.

All the while, in his capacity as SFRC chairman Corker enforced the ruinous bipartisan foreign-policy orthodoxy by structuring hearings in such a way as to rarely—if ever—allow room for dissenting option. As The Nation noted in March, under Corker’s watch, “congressional hearings merely function as a high-end salon for the foreign-policy establishment’s chattering class, enforcing conformity of opinion and narrowing the scope of acceptable policy options available to the president.”

But perhaps there is time for Corker to act on his newfound courage to challenge the powers that be. The Atlantic’s James Fallows writes that it is what Corker does next that matters; the Twitter spat, says Fallows, “most definitely should not be the last step for Corker. If he believes what he says, then as the chairman of the relevant committee in the Senate he has important tools to use. He can issue subpoenas and summon executive branch witnesses as soon as he can get his colleagues back in town. He can draft legislation about the procedure, the grounds, and the justifications before the U.S. commits troops to war.”

But given what we know about Corker’s record, that seems unlikely. But who knows? Trump just may yet bring out the best in the junior senator from Tennessee.