WASHINGTON — Witnesses at a high-profile congressional hearing on Islamic radicalization said Thursday that America is “failing” to confront the threat posed by homegrown extremism, as lawmakers traded accusations over whether the inquiry unfairly singled out Muslims.

Dr. M. Zuhdi Jasser, president of the American Islamic Forum for Democracy, said “paralysis” over the issue has seized the nation’s leaders and he urged the Muslim community to confront what he called an “exponential increase” in the number of Muslim radicals in the United States.

“The US has a significant problem with Muslim radicalization,” said Jasser, who is Muslim. “It is a problem that we can only solve.”

Rep. Peter King (R-N.Y.), chairman of the House Homeland Security Committee, clashed early with other lawmakers over the decision to hold the hearing, with one Democrat accusing King of “scapegoating” and King countering that his critics are spreading “rage and hysteria.”

The hearing aired a divergent set of views on the scope of the threat posed by radical Islam in the United States and the pertinence of holding a hearing focusing solely on that topic.

As the hearing got underway, King vowed to press ahead and said the hearing would be just the first in a series of hearings on homegrown terror. In his opening statement, King cited recent terror plots against the United States in defending his decision. He suggested the hearings could help fulfill the committee’s duty to “protect America from a terrorist attack” by examining the root of recent plots.

“This committee cannot live in denial,” King said, accusing critics of trying to “dilute” the focus by turning attention to groups other than al Qaeda.

“Only al Qaeda and its Islamist affiliates in this country are part of an international threat to our nation,” King said.

King said the hearings “must go forward, and they will,” adding backing down would amount to a “craven surrender to political correctness.”

But Rep. Keith Ellison (D-Minn.), the first Muslim ever to be elected to Congress, warned that the hearing could unfairly increase suspicion of Muslim Americans by lumping them together with violent extremists.

“When you assign their violent action to the entire community, you assign collective blame to a whole group,” Ellison said. “This is the very heart of stereotyping and scapegoating.”

Ellison broke down at the end of his testimony as he told the story of a Muslim-American paramedic who lost his life trying to rescue victims of the 9/11 terror attacks in New York City.

Ellison said Mohammad Salman Hamdani was vilified by the US media, which he said speculated that the 23-year-old was involved in the attacks. “It was only when his remains were identified that these lies were exposed,” Ellison said, breaking down in tears.

Rep. Bennie Thompson (D-Miss.), the ranking Democrat on the committee, said extremists could exploit the hearing and use it as “propaganda” to inspire a “new generation of suicide bombers.”

The hearing also featured tense moments between the lawmakers and the witnesses. Rep. Jackie Speier (D-Calif.) criticized the focus of the hearing and questioned the witnesses’ expertise on the subject.

Witness Melvin Bledsoe, whose son allegedly attacked an Army recruiting center in Arkansas, retorted, “I’m wondering how did [the lawmakers] get on the commission to speak about some of the things they’re speaking about.”

“We’re worried about stepping on their toes and they’re talking about stamping us out,” Bledsoe said of radical Muslims. “I’m wondering, ‘Why don’t the people pull their blinders off?'”

Jasser, the first witness Thursday, told Fox News ahead of the hearing that he believed King was being criticized because he was willing to look for a Muslim solution.

“All of a sudden, this becomes politically incorrect and they start attacking the messenger, Congressman King, they start attacking me and others rather than dealing with the hard medicine, the hard treatment of saying, ‘You know what? The majority of Muslims want to fix the problem but we have to figure out those that are feeding the problem, how to reform and bring them into modernity.'”

Jasser added that some misguided imams are conditioning Muslims to distrust the US government and as a result of political correctness, the nation is failing to prevent homegrown terror.

Bledsoe described how his son, Carlos, was radicalized when he went to college in Nashville, Tenn. Bledsoe explained how his son’s personality changed and how, when he returned home for the holidays in 2005, his son told his family that he converted to Islam, removed a photograph of Martin Luther King Jr. from the wall of his room and declared everything he would do from that point would be to honor Allah. Carlos Bledsoe later changed his name and eventually traveled to Yemen.

“Americans are sitting around doing nothing about radical extremism,” Melvin Bledsoe testified, describing it as “a big elephant in the room.”

“As you can see, a lot of people are still in denial that we even have a problem in America,” he added later. He said he hoped his testimony would help Americans prevent the radicalization of young people in their lives.

Abdirizak Bihi, whose nephew was one of approximately 20 Somali-American youths from the Minneapolis area who were radicalized and recruited by al Shabaab to travel to Somalia, said Muslim leaders intimidated him and urged him not to contact authorities.

Bihi said leaders from his mosque told him and the family members of the other youths that if they contacted the FBI or police, “they will send you to Guantanamo.” He also said the leaders said the youths would have a better chance at returning to the US if authorities were not contacted. In addition, he said the Muslim leaders said those who contacted the police would be responsible for the eradication of all mosques in the US and would “have eternal fire in hell.”

Following the hearing, King called it “extremely productive and worthwhile.”

“I am more convinced than ever that it was the appropriate hearing to hold,” the congressman said, adding he hoped critics realized the “mindless hysteria” that preceded it “did nobody much good.”

King said he would hold another hearing in a few months that would likely focus on the radicalization of Muslims within the US prison system.