AILSA CHANG, HOST:
OK. As we said earlier, President Trump today threatened to cut off or substantially reduce foreign aid to Honduras, Guatemala and El Salvador. That's where the migrants in the caravan we just heard about are coming from.
(SOUNDBITE OF ARCHIVED RECORDING)
PRESIDENT DONALD TRUMP: We give them tremendous amounts of money. You know what it is. You cover it all the time - hundreds of millions of dollars. They, like a lot of others, do nothing for our country.
CHANG: Also last week, Trump threatened to call up the U.S. military and close the southern border altogether. To find out if the president would be able to follow through on these threats, we're joined now by NPR's Scott Horsley at the White House. Hey, Scott.
SCOTT HORSLEY, BYLINE: Hi, Ailsa.
CHANG: So can the president on his own cut off aid to Central American countries, or does he first need cooperation from Congress?
HORSLEY: The president does have some latitude to curtail aid payments. Lawmakers might not like that. The top Democrat on the House Foreign Affairs Committee has already lodged a protest. But presidents in the past have used this power to hold up aid to countries they don't believe are acting in U.S. interests.
Now, aside from his authority, some of the experts I spoke with said it would be counterproductive for President Trump to follow through on this threat. They say cutting off aid might just make conditions in the Central American countries worse and create an even bigger push for people to try to pack up and escape to the north.
CHANG: Now, Trump has called on Mexico to stop the caravan and said that if that doesn't happen, he will call up the U.S. military and close the southern border. I mean, he is commander in chief, so can he unilaterally do that?
HORSLEY: Trump and other presidents have mobilized the National Guard in the past, usually in cooperation with state governors. You might remember that President Trump mobilized about 4,000 Guard troops this past spring to lend a hand with border security. In general, those Guard troops have been playing a support role. They're not actually patrolling or sealing the border.
But, Ailsa, that's not really the point. You know, the migrants the president's been talking about are not, as a rule, trying to evade the Border Patrol. On the contrary, they have been deliberately turning themselves in when they reach the border and asking for asylum. So it's not really clear what bringing in more troops would actually accomplish.
CHANG: He's also threatened to turn away migrants if they don't first apply for asylum in Mexico. Can he enforce that?
HORSLEY: Longstanding federal and international law says immigrants who present themselves at the border have the right to seek protection as refugees, at least to apply for it. And that's what many of these Central American migrants have been doing. Many of them are also doing so in family groups, and that has posed a challenge for the administration because of the limits we've talked a lot about on detaining young people, for example. We have seen a surge in the number of family groups crossing the border illegally. But we have to keep this in perspective. Overall, the level of illegal border crossings is still way down from its high point around the year 2000.
CHANG: OK, and as we heard in the interview with reporter James Fredrick just right now, migrant advocates are refuting Trump's claim that Democrats are to blame for the caravan. What do you know about? Are these threats just a ploy ahead of the midterm elections?
HORSLEY: The president has been claiming without evidence that Democrats want open borders. A lot of Democrats point to the 2013 bipartisan bill that passed the Senate that actually would've substantially beefed up border security. But that said, this is certainly an energizing issue for the president's base, and so it's no surprise he's stressing it not only on his Twitter feed but at the campaign rallies he's been holding around the country with just over two weeks to go before the midterm elections.
CHANG: All right, that's NPR's Scott Horsley. Thanks, Scott.
HORSLEY: You're welcome. Transcript provided by NPR, Copyright NPR.