WASHINGTON (CNN) -

Is a law designed to protect children from human trafficking actually causing a humanitarian crisis along the U.S. southern border, allowing thousands of children to illegally surge into the United States?

Amid the crisis and calls to change the law, one of its chief backers defends it.

"I was very proud to be apart of the sponsoring" of the law, Rep. Jeff Fortenberry, R-Nebraska, told CNN's Michael Smerconish in an interview Saturday. "Human trafficking is a modern form of slavery."

The William Wilberforce Trafficking Victims Protection Reauthorization Act of 2008 added protections for unaccompanied minors who entered into the U.S. illegally. It applied to children from nations that do not border the United States. Child immigrants from Honduras, El Salvador and Guatemala have crossed into the U.S. en masse, this year. Because of the law, those child immigrants are not immediately processed for return to their country, whereas children from Mexico are immediately readied for return.

Many -- including some Republicans -- insist the law is partly responsible for the unaccompanied children pouring into the U.S., and that tweaking the law will stem the flow.

Fortenberry, instead lays much of the blame at President Barack Obama's feet.

"This problem with the surge of children and families at the border did not occur until 2013," Fortenberry said. "[It] did not occur in '08, '09, '10, or '11."

"Five years after this, the reality is this is a convergence of factors of desperate poverty, ungoverned space, as well as an exploitation of our laws. And the president fostered an environment in which in 2012, he suggested that deportations were going to decrease. And I think that was a corollary to [the] exploitation of this law and other factors that have led to this sad, sad, tragic situation along the border."

Smerconish pressed the congressman on whether or not the law he backed needs to be changed, as even members of his own party have said.

"It is my understanding buried within the '08 law, there is a provision that allows the president to negotiate with the Central American countries repatriation agreements, and that hasn't happened," he said. There may be a need to actually fix that portion of the law so that that aspect of the dynamic which has fostered the conditions for the surge of children can stop. But the first thing that needs to happen is some leadership."

He said that if he could offer advice to the President, it would be to "send National Guard troops to the border, that he help back up the Border Patrol and get the situation under control."

Meanwhile, will the congressman back the president's request for $3.7 billion in emergency immigration funds?

"We're not simply going to give a blank check," Fortenberry said. "We have to go through this methodically in a sound way to restore order in a situation that's chaotic."