Meghan McCain looks to fallen soldier's father 'for answers' to Trump's attacks against her dad
WATCH: The Gold Star father and Meghan McCain discuss how to handle public attacks from the president.

Gold Star dad Khizr Khan -- who came under fire from then-candidate Donald Trump after decrying his proposed ban on Muslim immigrants -- condemned the president's recent comments bashing the late Sen. John McCain, with whom he had a long-standing feud.

"How dare this Russian-tainted president disrespects our hero," Khan told Meghan McCain on "The View" about Trump's attacks on the late senator. Trump recently railed on McCain, who died last summer, both on Twitter and in a speech at a tank manufacturing plant.

"Senator McCain has meant so much to this nation because of his sacrifice -- because of his family's sacrifice and service," added Khan, whose son, an Army captain, was killed in Iraq. "We have been elevated because of his family and senator McCain."

Khan's praise for McCain comes nearly three years after he spoke out against Trump, then the Republican nominee, at the Democratic National Convention saying he "sacrificed nothing" for his country.

In a 2016 interview with ABC News' George Stephanopoulos, Trump declared he's "made a lot of sacrifices," questioned if "Hillary's scriptwriters [wrote]' Khan's speech, and insinuated that Ghazala didn't speak during her husband's speech because of her religion.

During the public feud between Trump and Khan in 2016, Sen. McCain spoke out in support of Khan's family and condemned Trump's attacks on him.

"Arizona is watching. It is time for Donald Trump to set the example for our country and the future of the Republican Party," the Arizona senator and 2008 GOP presidential nominee said in a statement. "While our party has bestowed upon him the nomination, it is not accompanied by unfettered license to defame those who are the best among us."

On "The View" Monday, Khan told Meghan McCain he was "honored to sit under" the "grace" and "dignity," of Senator McCain's family, who he calls a "hero of this nation."

Khan's son Humayun Khan was a University of Virginia and ROTC graduate, U.S. Army captain and war hero. In 2004, Khan's son lost his life stopping a suicide bomber while serving in Iraq.

Posthumously, Humayun was awarded a Purple Heart and Bronze Star for his actions.

The relationship between Khan and John McCain dated back to 2005, about year after his book "Why Courage Matters: The Way to a Braver Life" was published. Khan revealed on "The View" that McCain's book was the last book he sent to his son to read, and it ended up being the topic of the last conversation he would ever have with his son.

"I asked [Humayun] in my last conversation, 'Did you receive the book?' He said, 'It's a wonderful book. All of my camp is reading it and we are encouraged,' Khan said. "That is Senator McCain."

"This president forgot to read about the chapter that teaches how to be commander-in-chief of the United States. Somebody should read it to him," he continued. "So he can learn to take care of those who have sacrificed so much."

The president took a number of jabs at the late senator this month, including calling him out for being “last in his class," saying he was “never a fan” and that he “never will be” after McCain voted against repealing Obamacare, and bashing him for not receiving proper credit for his funeral arrangements.

Last week, Meghan McCain said she's "emotionally exhausted" from responding to Trump's attacks on her late father, but no longer expects 'decency' from the president's family.

“Attacking someone who isn’t here is a bizarre low,” McCain said. “My dad’s not here but I’m sure as hell here.”

Every episode of ABC's award-winning talk show "The View" is now available as a podcast! Listen and subscribe for free on Apple Podcasts, Google Podcasts, TuneIn, Spotify, Stitcher or the ABC News app.