Lt. Col. Alexander Vindman, a national security council Ukraine specialist and his brother Yevgeny, a national security lawyer who was not involved in the Ukraine controversy, were sent back to the Pentagon. US ambassador to the European Union Gordon Sondland, who effectively implicated Trump in a quid pro quo in colorful House testimony, was also sent packing. The two had been quietly planning exits of their own, three sources told CNN's Kaitlan Collins, but according to a person familiar with Trump's thinking, although he had been advised to simply let them leave to avoid the criticism of firing impeachment witnesses, he didn't want them to go quietly.
Republican senators have correctly pointed out that the President has the power to fire anyone in the executive branch and has the right to a team in which he has confidence.
"He's a political appointee. He serves at the pleasure of the President," South Carolina Sen. Lindsey Graham said on CBS' "Face the Nation" on Sunday, referring to Vindman.
Yet Trump's moves, conducted so quickly after the ending of the impeachment showdown were a clear sign that those who cross him will pay a price -- in a way that could send a chill through the government and stifle dissent and accountability. And they undermine the comments of GOP senators who in voting to acquit the President suggested that the shame of impeachment could temper his behavior.
Similarly, Trump's vocal attacks on Mitt Romney, the sole senator in history to vote to convict a President of his own party, send an unmistakable warning to the GOP: the President demands total loyalty. Those who refuse are ostracized.
Trump is also set to ignore another constitutional norm -- that Congress has the power of the purse -- by diverting billions more in already appropriated funding to pay for his border wall. The administration argues it does not require the approval of lawmakers for such steps. But lawmakers from both parties have complained about losing funding for projects within their own states and have argued the practice is symptomatic of a wider transfer of power from Capitol Hill to the White House.