It came across Donald Trump's Twitter feed early Tuesday morning, seemingly out of the blue: a demand that flag burners should face consequences, including jail and maybe even the loss of their citizenship.

The Republican president-elect's tweet rattled civil liberties and legal experts, who were quick to note that the Supreme Court ruled long ago that flag desecration is considered free speech and that it is unconstitutional to punish someone by stripping his or her citizenship.

But whatever Trump had in mind, the president-elect's outburst underscored a key aspect of his three-week-old transition: He is continuing to cater to his base - the largely white, working-class voters who propelled him to the White House - with relatively few overtures to the majority of voters who cast ballots against him.

"Trump won rural America, where support of the flag is a big issue," said Scott Reed, a longtime Republican strategist who served as Bob Dole's campaign manager in 1996. "A lot of those homes that had Trump signs out front were also flying American flags. This is clearly part of his base politics."

The same dynamic will play out Thursday when Trump kicks off a "Thank You Tour" with a campaign-style rally of supporters in Ohio.

Aides have suggested the tour will include other states where the Republican prevailed, including some traditionally Democratic ones where he won in part by driving up the rural white vote.

Since defeating Hillary Clinton in electoral college votes on Nov. 8, Trump has made some efforts to reach out beyond his base with cabinet picks that have pleased the GOP establishment. Those include Elaine Chao, a former labor secretary and the wife of Senate Majority Leader Mitch McConnell (R., Ky.), whom Trump announced as his transportation secretary on Tuesday.

But there has been little in Trump's actions so far to suggest that he is courting the Democrats who voted against him - or working to shore up an approval ranking still in negative territory.

Trump did not say Tuesday what inspired his tweet about flag-burning, but it came just days after a college in western Massachusetts decided to stop flying the U.S. flag in response to students there burning one in protest of Trump's election.

Hundreds of veterans and others gathered Sunday to protest the decision by Hampshire College in Amherst, Mass.

A segment on the controversy aired Tuesday on Fox News' Fox & Friends shortly before Trump's 6:55 a.m. tweet went out.

"Nobody should be allowed to burn the American flag - if they do, there must be consequences - perhaps loss of citizenship or year in jail!" Trump wrote in a tweet that by late afternoon Tuesday had been "liked" by more than 145,000 people.