An unrepentant Rep. Steve King (R-Iowa) took to the House floor on Thursday afternoon to defend his opposition to immigration reform and challenge his critics to debate him on the issue.

King delivered a 20-minute speech on the historical origins of the United States, including the importance of debate and voicing of contrary views. King said everyone should be open to debate to learn more and, if needed, correct their own misconceptions.

"I challenge people to debate with me because I believe one of two things," King said. "If I can't sustain myself in debate, I need to go get some more information, I need to get better informed, or could it be that I'm wrong?"

King has been on the hot seat since the weekend, when he criticized supporters of reform for depicting immigrants as law-abiding achievers, arguing that many criminals would also benefit from a pathway to citizenship.

"For everyone who's a valedictorian, there's another 100 out there that they weigh 130 pounds — and they've got calves the size of cantaloupes because they're hauling 75 pounds of marijuana across the desert," he said. "Those people would be legalized with the same act."

Those comments led to sharp criticism from both Republicans and Democrats, and even Speaker John BoehnerJohn Andrew BoehnerRestoring fiscal sanity requires bipartisan courage GOP congressman slams primary rival for Ryan donations Speculation swirls about Kevin McCarthy’s future MORE (R-Ohio), who called King's remarks “deeply offensive and wrong,” said they would make immigration tougher to deal with in Congress.

King on Thursday said he believes his views on immigration policy are correct.

"Our southern border is porous," he said. "It's not as porous as it was seven or eight years ago, mainly because the economy has grown in Mexico at about twice the rate that it's grown in the United States over the last four and a half or five years."

"Eighty to 90 percent of the illegal drugs consumed in America come from or through Mexico," he continued. "I can tell you that in Mexico they are recruiting kids to be drug smugglers, between the ages of 11 and 18.”

King added that Mexico incarcerates about 800 children for trafficking drugs per year, and that the U.S. also catches some.

"Every night, some come across the border, smuggling drugs across the border," he said. "The media is replete with this."

King ended by urging policymakers to be critical thinkers on the issue.

"No nation like the United States of America can continue to grow and be a strong nation if we are going to judge people because they disagree with our agenda rather than the content of their statement," he said. "We have to be critical thinkers, we have to be analytical, we should understand facts from emotion."