Rep. Peter King (R-N.Y.), chairman of the House Homeland Security Committee, testified before Parliament Tuesday in a session that was, at times, combative and testy.

King was invited by the British committee to discuss his investigations into radicalization in American Muslim communities. The topic has been a hot-button one in Britain in the wake of summer riots that tore through London. But members of Parliament questioned whether his investigations turned an unfair spotlight on Muslim-Americans.

King quickly dismissed the idea.

"Undoubtedly, congressional investigation of Muslim-American radicalization is the logical response to the unquestionable fact that homegrown radicalization is part of al Qaeda’s strategy to continue attacking the United States and its allies,” King said. “I would not back down to political correctness.”

The theme of "political correctness" was one King hammered, saying that he was “concerned that within the United States, political correctness has prevented many from sufficiently acknowledging and tackling this dangerous problem."

But MPs also questioned why King — who made comments in the 1980s highly supportive of the Irish Republican Army, which was linked to domestic bombings that killed civilians in Ireland — was heading terrorism investigations in the House. David Winnick, a Labour Party member, asked King if he stood by remarks in which he said that he would not hold the IRA morally responsible for civilian deaths in a military attack.

"I was trying to put it in a perspective to show that there were people — that this is not just the terrorist mayhem it was made out to be — that there were significant leaders on the Republican side," King said defending his comments.

King was the first member of Congress to testify before the House of Commons, according to his office.