The casket is pictured leaving the memorial service of U.S. Senator John McCain (R-AZ) at National Cathedral in Washington, U.S., September 1, 2018.

A grief-stricken Meghan McCain appeared to take a swipe at President Donald Trump during a moving tribute honoring her father, Arizona GOP Sen. John McCain, blasting the president for "cheap rhetoric" on American greatness.

At the Washington National Cathedral on Saturday, the senior McCain got a heroes salute from both of the men he sought to defeat politically, former presidents Barack Obama and George W. Bush.

While holding back tears, the senator's daughter voiced a stinging rebuke that was directed at some of her father's detractors, including Trump. She articulated her father's vision of how he saw the nation during his service, appropriating the president's "Make America Great Again" campaign slogan.

"The America of John McCain has no need to be made great again because America was always great," she later said.

In describing her father, Meghan McCain said he was "American greatness, the real thing, not cheap rhetoric from men who will never come near the sacrifice he gave so willingly, nor the opportunistic appropriation of those who lived lives of comfort and privilege while he suffered and served."

During her tribute, she never mentioned the president by name.

Trump infamously questioned the veteran Republican Senator's military credentials during the 2016 election cycle, stoking outrage by suggesting McCain was not a hero because he was captured by the Vietnamese.

McCain survived more than 5 years of torture and imprisonment during the Vietnam War before going on to serve more than three decades in Congress, both as a member of the House and as a senator. He was known for his ferocious opposition to policies that didn't match his principles and for taking on presidents, no matter their party.

Members of the Trump administration, including son in law Jared Kushner and daughter Ivanka, were present at the service.