David Jackson

USA TODAY

Donald Trump, under steady criticism from the father of a Muslim U.S. Army captain killed in Iraq, tried Sunday to clarify his remarks about the family of the late Captain Humayun Khan.

“Captain Humayun Khan was a hero to our country and we should honor all who have made the ultimate sacrifice to keep our country safe," Trump said in a statement. "The real problem here are the radical Islamic terrorists who killed him, and the efforts of these radicals to enter our country to do us further harm."

The statement came in the wake of an ABC News broadcast Sunday in which Trump appeared to criticize Khizr Kahn, the late captain's father, after he went after Trump during the Democratic convention that nominated Hillary Clinton last week. Trump's remarks on ABC and his subsequent comments on social media brought another tsunami of bipartisan criticism.

Clinton led the way Sunday during an appearance at a church in Cleveland.

"Mr. Khan," she said, pausing, "paid the ultimate sacrifice in his family, didn't he. And what has he heard from Donald Trump? Nothing but insults degrading comments about Muslims, a total misunderstanding of what made our country great, religious freedom, religious liberty. It's enshrined in our Constitution, as Mr. Khan knows, because he's actually read it.

"And we have no religious test for political office in America. Among our great strengths is our diversity of belief, of background, of race, of creed, of ethnicity," Clinton said.

Last Thursday at the Democratic National Convention in Philadelphia, Khizr Khan urged Trump to read the U.S. Constitution and said of New York businessman: "You have sacrificed nothing and no one."

"Who wrote that?" Trump said when asked about the comment on ABC's This Week. "Did Hillary's script writers write it?"

He also told ABC that Khan was "very emotional and probably looked like a nice guy to me."

Trump struck a harsher note on Twitter, saying Sunday that "I was viciously attacked by Mr. Khan at the Democratic Convention. Am I not allowed to respond? Hillary voted for the Iraq war, not me!"

In the ABC interview, Trump noted that Khan's wife Ghazala stood at his side during the speech and said nothing, and suggested that she was not allowed to speak.

"She had nothing to say," Trump said. "She probably ... maybe she wasn't allowed to have anything to say. You tell me."

Ghazala Khan, who helped write her husband's speech, said it has been difficult to speak about her son's death publicly. In an article for The Washington Post, she wrote that "when Donald Trump is talking about Islam, he is ignorant."

Khizr Khan did not back down from his comments during an appearance on NBC's Meet The Press, saying that "we have a candidate without moral compass, without empathy for its citizens."

While he said he appreciated Trump's description of his son as a "hero," Khan told NBC that "it sounds so disingenuous because of his policies, because of his rhetoric of hatred, of derision, of dividing us. And that is why I implored him to read the constitution."

Trump's comments were attacked by many of his Republican critics, including Ohio Gov. John Kasich.

Dad of Muslim soldier: Trump should read the Constitution

"There's only one way to talk about Gold Star parents: with honor and respect," Kasich tweeted. "Capt. Khan is a hero. Together, we should pray for his family."

Senate Majority Leader Mitch McConnell of Kentucky released a statement Sunday saying he opposed Trump's call for a ban on Muslims traveling to the United States. "Captain Khan was an American hero," McConnell said.

Peter Wehner, a former aide to President George W. Bush, said on Twitter: "Memo to Trump supporters: He's a man of sadistic cruelty. With him there's no bottom. Now go ahead & defend him."

In his follow-up statement Sunday, Trump said the real issue is "radical Islamic terrorists," and that is why he has called for restrictions on migration into the United States.

"We have to know everything about those looking to enter our country, and given the state of chaos in some of these countries, that is impossible," Trump said.

He also had choice words for the elder Khan: "While I feel deeply for the loss of his son, Mr. Khan who has never met me, has no right to stand in front of millions of people and claim I have never read the Constitution, (which is false) and say many other inaccurate things."

Contributing: Heidi Przybyla

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