Retired general gets emotional as he unloads on Lindsey Graham for smearing Lt. Col. Alexander Vindman

Retired Brig. Gen. Peter Zwack served as a mentor to Lt. Col. Alexander Vindman, who has ended up as the target of President Donald Trump's revenge for the impeachment over the Ukraine scandal.

Speaking to CNN Monday, Zwack recalled when he was serving in Afghanistan and Sen. Lindsey Graham (R-SC) came to see the troops along with Sens. John McCain (R-AZ) and Joe Lieberman (I-CT).

"We thought you guys were rockstars," Zwack said. "Where are you now, sir?"

Zwack's disappointment with Graham stems from a weekend interview where the South Carolina senator blamed Vindman and people like him in the so-called "Deep State" for partisan political attacks on the president.

Vindman served under Zwack in Moscow for "two very difficult years," he said.

"I know Alex. I've known him for a long time," he told CNN's Brooke Baldwin. The two have spoken about three times over the last several months, "usually after, if you will, an assault on his character."

Zwack said that he thinks Vindman is "hurt" and "insulted," while also being "uncertain about his future."

"He wears the uniform proudly and he's uncertain of that future as well," the former general said. "I think that seniors at a very, very high level should not dumped that way publicly by statement or the god-gun of a tweet, in demeaning his personality."

Zwack got a little emotional, saying that one thing that "offends him greatly" is "so many other people have piled in that don't even know him."

Baldwin noted that she could hear the emotion in his voice and see it in his eyes.

See the exchange below: