Donald Trump referred to Democrats who didn’t clap at his State of the Union address on Jan. 30 as “treasonous” in a speech in Ohio today.

While Republicans were “going totally crazy wild,” during the speech, Democrats were “like death,” Trump said, referring to the way that some members of Congress sat quietly during his address. “[It’s] un-American. Somebody said treasonous,” he continued.

“Can we call that treason? Why not?” he asked the crowd.

The Congressional Black Caucus and the Democratic women in Congress both wore black for Trump’s State of the Union speech, and rarely applauded during it. They presented a marked contrast to the Republican side of the room, nearly all older white men in suits who leapt to their feet cheering throughout the speech, with a few chanting “USA! USA!” toward the end.

Fox News hosts have also criticized Democrats for not applauding Trump. But their unenthusiastic reaction isn’t unusual.

One side of the room or refusing to give a president a standing ovation during the State of the Union speech is a Congressional tradition that goes back decades. Here’s the view from the back of the House chamber during president Bill Clinton’s 1999 State of the Union speech, with Republicans seated on the right (some do appear to be clapping), and Democrats standing and clapping on the left.

Just months after the terrorist attacks of Sept. 11, 2001, George W. Bush’s first State of the Union appeared to be an anomaly in modern history. He earned a standing ovation from both sides, during remarks on fighting terrorism.

Reuters/Mike Theiler Both sides stand for the end of George W. Bush’s speech in January of 2002.

Republican reactions during Barack Obama’s State of the Union speeches were much more muted, according to newswire coverage, with the Republican side often failing to applaud his remarks during the speech. Below, the Republicans are on the left side of the photograph, Obama’s cabinet is standing in the front row, and Democrats are on the right.

AP Photo/Pablo Martinez Monsivais Democrats stand, Republicans sit, as Obama speaks in the 2010 SOTU.

Again in 2016, Republicans on the left side of the photo sit as Obama speaks, some applauding, some with their hands in their laps, while many Democrats on the right stand and cheer his remarks.

Reuters/Jonathan Ernst Split house.

Trump’s State of the Union speech focused on “unity” but he’s spent the past few days on Twitter and in public remarks mocking Democrats individually and as a group. On Thursday, Congress needs to vote in a new budget or the government will shut down, and the Republicans that control both houses need Democratic support for it to pass.