Fox News contributor and former Acting ICE Director Tom Homan joined Harris Faulkner on "Outnumbered Overtime" Thursday to react to President Trump's warning that he could use the U.S. military to close the southern border with Mexico if officials there don’t stop a growing migrant caravan that's swelled in size to about 4,000 people.

The president’s latest threat against the caravan that originated in Honduras – and which is heading to the U.S. in a bid to escape Honduras’ poverty and violence – comes as Secretary of State Mike Pompeo is heading to Central America to talk with leaders about the issue.

"I think the president threw down the gauntlet, as he should have," Homan said, predicting that the Mexican government will "do the right thing" and not allow the caravan to pass through.

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Noting that Mexican officials have deployed 500 additional federal police officers to the Mexico-Guatemala border, he predicted they will either turn the caravan back or let the migrants apply for asylum in Mexico.

"If these people are really concerned about persecution, fear and death and they want to claim political asylum, they are now out of Honduras. They have crossed through Guatemala and they'll get to Mexico," Homan said. "It's really not about persecution or fear. It's about getting to the United States and committing fraud."

As for Trump's threat to shut down the border, Homan said it's "certainly an option," noting that President Reagan shut down a large portion of the border in the 1980s after a DEA agent went missing in Mexico and the Mexican government was uncooperative.

Just a few weeks away from November's midterm elections, Homan said he hopes immigration enforcement and border security are issues voters take to the polls.

"This is right at the doorstep of Congress. And the Democrats -- I've gotta agree with the president -- they want open borders. They want to abolish ICE, which equals open borders," Homan said. "I hope the American people are paying attention."

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