In late July, just two days before casting the deciding vote against his party’s regressive health care agenda, Sen. John McCain (R-Ariz.) delivered a striking speech on his concerns about contemporary politics and what’s become of the legislative process. That the veteran senator had just been diagnosed with brain cancer made his remarks that much more dramatic.

McCain’s medical treatments have apparently gone well, and the Arizona Republican will return to Capitol Hill when Congress gets back to work on Tuesday. But before lawmakers’ summer break ends in earnest, McCain published an op-ed in the Washington Post, returning to some of the themes he stressed on the Senate floor on July 26.

Congress will return from recess next week facing continued gridlock as we lurch from one self-created crisis to another. We are proving inadequate not only to our most difficult problems but also to routine duties. Our national political campaigns never stop. We seem convinced that majorities exist to impose their will with few concessions and that minorities exist to prevent the party in power from doing anything important. That’s not how we were meant to govern. Our entire system of government – with its checks and balances, its bicameral Congress, its protections of the rights of the minority – was designed for compromise. It seldom works smoothly or speedily. It was never expected to.

All of this is easy to embrace and not at all controversial. What stood out as especially notable in the piece, however, were the not-so-subtle shots the senator sent across Donald Trump’s bow.

“Congress,” McCain wrote, “must govern with a president who has no experience of public office, is often poorly informed and can be impulsive in his speech and conduct.”

And then he went just a little further.

“We must respect his authority and constitutional responsibilities. We must, where we can, cooperate with him. But we are not his subordinates. We don’t answer to him,” McCain added. “We answer to the American people. We must be diligent in discharging our responsibility to serve as a check on his power. And we should value our identity as members of Congress more than our partisan affiliation.”

For Trump critics, this no doubt sounds encouraging, and I imagine we’ll see another round of headlines about McCain being a “maverick.” But it’s hard to say with confidence whether, and to what extent, he intends to follow through.

Those who follow politics closely have probably noticed a pattern when it comes to circumstances like these: John McCain will signal a degree of independence, receive plaudits from pundits, but fall back into partisan habits almost immediately thereafter.

This has been true throughout the year. When Trump nominated Rex Tillerson, who’s enjoyed close ties with Vladimir Putin’s Russian government, to serve as Secretary of State. McCain was asked whether there was a “realistic scenario” in which he’d vote to confirm such a nominee to serve as the nation’s chief diplomat. “Sure,” the Arizona Republican replied. “There’s also a realistic scenario that pigs fly.”

Soon after, McCain voted for Tillerson anyway.

This wasn’t an isolated incident. The longtime GOP senator frequently generates attention by raising “concerns” about various partisan priorities, but McCain’s actions haven’t consistently matched his rhetoric.

Maybe developments in August have shaken the senator’s perspective. Perhaps we’re poised to see McCain challenge Trump in many of the same ways he challenged the Bush/Cheney White House in early 2001.

I don’t know what we’ll see from him in the coming months, but I suppose writing in the Washington Post that Trump is an inexperienced, ignorant, and impulsive president is a decent start.