President Donald Trump’s strategy for escaping removal from office in the House impeachment inquiry is simple, according to mainstream media: Attack the witnesses.
“Eight weeks into the House impeachment inquiry, President Trump and many of his allies have seized on a core defense strategy by attacking career public servants who are testifying as witnesses in the probe and spreading disinformation about their motives as ‘unelected bureaucrats,’” wrote Elise Viebeck and Isaac Stanley-Becker of the Washington Post in “Attacking witnesses is Trump’s core defense strategy in fighting impeachment.” 
CNN put it down to worry on the president’s part. “President Donald Trump’s impeachment angst led him to fire off a new attack on a key witness and threatens to deepen in the frenetic week ahead with crucial testimony scheduled from officials caught in the middle of the Ukraine storm,” wrote Stephen Collinson in “Trump attacks another witness as his impeachment defense faces new tests.” 
He’s making it harder on himself, wrote the New York Times. “House Republicans, bracing for another week of impeachment hearings, asserted on Sunday that President Trump has done nothing wrong because his plans for Ukraine to investigate his political rivals never came to fruition – even as the president complicated their efforts by attacking another witness,” wrote Sheryl Gay Stolberg of the Times under the headline: “Republicans Shift Defense of Trump While He Attacks Another Witness” – subhead: “With Gordon Sondland prepared to testify this week, Republicans backed away from complaints about secondhand information and instead offered a blunter defense: The president did nothing wrong.” 
Slate focused on the tweet Trump sent when Marie Yovanovitch, former ambassador to Ukraine, was on the stand before the House Permanent Select Committee on Intelligence. It wrote  that Trump “assailed the witness at the stand,” which was not true. He was at the White House, and the witness would not have known about the tweet during the hearing except that Rep. Adam Schiff (D-Calif.), read it aloud to her from the dais.
It said  the tweet – which read: “Everywhere Marie Yovanovitch went turned bad. She started off in Somalia, how did that go? Then fast forward to Ukraine, where the new Ukrainian president spoke unfavorably about her in my second phone call with him. It is a U.S. president’s absolute right to appoint ambassadors.” – “echoed the talking point that pro-Trump spam accounts had already been making earlier in the hearing.”
In the Post’s story , Sen. Ron Johnson (R-Wisc.), was said to have “laid out criticisms against Lt. Col. Alexander Vindman” and “wrote without evidence that Vindman may be a member of a rebellious ‘deep state’ that ‘never accepted President Trump as legitimate’ and is working in secret to end his presidency.”
There is evidence. Vindman was reprimanded by a superior officer  for making jokes at the expense of Americans and the United States, supporting President Obama to an extent that made people in the room feel uncomfortable and conducting himself unprofessionally.
Other criticisms have emerged as Sen. Johnson’s letter “intensifies a campaign of attacks on Vindman  from Trump and his allies, which has included speculation about the decorated war veteran’s patriotism from conservative commentators and a White House statement on Friday criticizing his job performance,” the Post wrote . “Moves such as these have gained significant traction with Trump’s base, feeding into an echo chamber that stokes supporters’ resentments, broadcasts a single pro-Trump message and demonstrates the power of the online juggernaut Democrats will confront during Trump’s 2020 reelection campaign.”
It pointed to attacks on the “career public servants cooperating with the House impeachment inquiry,” in particular, the tweet by Donald Trump Jr. last week that said , “America hired him to fire people like the first three witnesses we’ve seen.”