Breitbart started out as a small site bent on exposing the liberal bias in mainstream media. Now, its former executive, Stephen Bannon, is in the White House, and the site has begun targeting political adversaries of the Trump administration. (Erin Patrick O'Connor/The Washington Post)

The seeds of Breitbart’s resentment were sown months before President Trump cut down chief strategist Stephen K. Bannon this week. Now the question is whether the hard-right news site that cheered Trump to victory — and sent Bannon, its former chairman, to the White House — will turn on the president.

Trump has disappointed Breitbart over and over since winning the election, but the site has pulled punches almost as often. With Bannon’s influence in the West Wing greatly diminished, according to a Washington Post report Wednesday night, Breitbart’s willingness to hold back could shrink, too.

Bannon could ultimately decide Breitbart’s direction, himself, if he were to quit — something he has reportedly threatened to do — or if he were fired. He could go the way of Corey Lewandowski, who as a TV commentator remained a fierce advocate for Trump, even after being dismissed as campaign manager last summer. Or Bannon could seek vengeance.

Signs of Breitbart’s aggravation with Trump were visible on the site’s homepage Thursday morning. The headline on an article by conservative commentator Ann Coulter, who has been a Trump booster, read: “LASSIE, COME HOME! WE WANT ‘PRESIDENT OF AMERICA,’ NOT ‘PRESIDENT OF THE WORLD.’ ”

“Trump’s Syrian misadventure is immoral, violates every promise he ran on, and could sink his presidency,” Coulter wrote.

Reminder: This is published on Breitbart.

Another article, from the Associated Press, bore this headline: “TRUMP CRITICISM OF BANNON WORRIES BASE.”

Breitbart has been worried for a while.

Two weeks after Trump defeated Hillary Clinton, Breitbart flipped out when Kellyanne Conway, who had managed the campaign down the stretch, told MSNBC that the president-elect “doesn’t wish to pursue … charges” against his former opponent. Trump warned Clinton during a debate that she would “be in jail” if he were president, and on the trail he often whipped his crowds into frenzied chants of “lock her up!”

“BROKEN PROMISE,” read a headline on Breitbart’s homepage. (The site loves all-caps.)

Breitbart absolutely hated Trump’s selection of Betsy DeVos as secretary of education — and published no fewer than five articles on the subject. The site called her a supporter of Common Core state standards, which conservatives despise and Trump campaigned against. (DeVos denied supporting Common Core.)

Breitbart strongly opposed the ill-fated Republican health-care plan backed by Trump, noting (correctly) that it did not amount to a full repeal of the Affordable Care Act. Trump campaigned on repealing and replacing Obamacare.

And even before the Coulter column, the fervently nationalistic Breitbart highlighted criticisms of Trump’s decision to strike Syria by the likes of conservative commentators Michael Savage and Pamela Geller and Sen. Rand Paul (R-Ky.).

All the while, Breitbart has been careful not to hit Trump too hard. The site’s staff writers have refrained from slamming the Syria strike in their own voices, sticking to commentary like this, from Joel B. Pollak: “Whatever the pros or cons of Trump’s decision, he promised to take action, and he followed through. Trump thus restored American credibility in the international arena.”

Breitbart disagreed with Trump on the health-care bill but blamed House Speaker Paul D. Ryan for its failure and for persuading Trump to get behind it, allegedly on false pretenses.

There is always an excuse — or has been, until now. At least Trump is decisive! It’s someone else’s fault!

Now that Trump is running out of patience with Bannon, we’ll see if Breitbart runs out of free passes for Trump.