Jong Yang:

As we reported earlier, the president says he want to send thousands of National Guard forces along the U.S. border with Mexico.

While Mr. Trump's plan has raised concerns, there is precedent. Both Presidents George W. Bush and Barack Obama sent troops to the southern front during their terms.

We get two takes from experts involved in both of those deployments.

John Sandweg worked at the Department of Homeland Security during the Obama administration. And Theresa Cardinal Brown advised the Bush administration's Department of Homeland Security.

Welcome to you both.

I want to ask each of you — and start with you, Theresa, about your decisions, the decisions made when under your administration, when you were working for the administration. George — President George W. Bush sent 6,000 troops to the border in 2006.

What were you trying to accomplish then and what was the situation that prompted this decision, and how does it compare to today?