"What (the ad is) trying to do is it's trying to show that we do have a real security threat on our borders," Short told CNN's "New Day." "I think what you saw last week, the report from (Department of Homeland Security) says there 2,500 people on the terror watchlist trying to get into the United States each and every year. That means seven per day that are either apprehended or turned away. We have serious security concerns and it's being ignored in a lot of this debate right now. We want to help get that resolved."
On NBC's "Meet the Press" Sunday, Short similarly defended Trump's stance on immigration, but noted
that the commercial was "done from a political organization. It's not done from people working inside the White House."
The 30-second video
was released hours after the government shutdown began. The immigration debate is the largest point of contention between the parties.
The Department of Justice and Department of Homeland Security report
Short cited focused on 549 individuals convicted of offenses between September 11, 2001, and December 31, 2016. But it included terrorist acts committed abroad (though it didn't say exactly how many), doesn't provide a breakdown of how many individuals were arrested for acts committed on US soil and doesn't explain how many foreign nationals were radicalized only after entering the US.
But Short also said the Trump administration is making "significant progress" on immigration negotiations to re-open the federal government.
"I feel like there's been significant progress. I think Democrats have moved significantly toward our position of the physical barriers that we're asking for," Short said on "New Day." "What's so hard for us to understand why we're having a manufactured shutdown when you're having progress in negotiations."
Speaking to reporters at the White House later Monday morning, Short called Democrats "hostage-takers," adding that Trump has continued to reach out to some members of the party.
Democrats have dug in against the Republican-offered proposal to fund government, asking instead to address immigration legislation either ahead of or in the same measure.
On Monday at noon, the Senate is set to hold a procedural vote on re-opening the government.