Former New York City Police Commissioner Bernie Kerik hammered America's liberal city leaders for defending sanctuary city policies that he said prioritize "partisan politics" over national security.

"The immigration issue -- it's a political issue," said Kerik on Fox Nation's "Deep Dive" on Thursday. "[It] shouldn't be a political issue. ... The polarized politics of the country is leading the argument versus the reality of national security."

U.S. Attorney General William Barr announced on Monday that the Justice Department will sue U.S. states that flout federal immigration law by refusing to cooperate with federal law enforcement. Specifically, the DOJ rolled out new legal actions against the states of California and New Jersey and King County in Washington state.

On Thursday, Immigration and Customs Enforcement (ICE) subpoenaed the state of Connecticut for information on multiple illegal aliens arrested there.

In his remarks, Barr said "so-called progressive politicians" are "jeopardizing the public's safety by putting the interests of criminal aliens before those of law-abiding citizens."

"What we're seeing here that we've never really seen before, other than maybe in the '60s certain protest movements, is chief law enforcement officers of the state, attorney generals or police chiefs or even mayors ... saying let's make an exception -- playing on the heartstring issue here," said federal criminal defense and civil right attorney David Schoen.

Schoen argued that sanctuary city leaders are guilty of the "emotionalization" of the immigration issue, by suggesting that they are protecting illegal immigrants from harm, by effectively shielding them from federal law enforcement.

Fox Nation host and Fox News contributor Tammy Bruce observed that, in fact, sanctuary cities may make immigrant communities more dangerous.

"What has perplexed me about the position of sanctuary cities is that those are the communities that are victimized first," she said. "So if we're really concerned about illegal aliens, undocumented workers, particularly women and children as well, that thinking about the impact on those individuals has to come first and foremost."

The U.S. Attorney for Arizona, Michael Bailey, held a news conference on Tuesday to announce the findings of his office's review of illegal immigrants, who were captured reentering the U.S. after they've already been deported.

BARR ANNOUNCES SWEEPING NEW SANCTIONS, 'SIGNIFICANT ESCALATION' AGAINST LEFT-WING SANCTUARY CITIES

Bailey said in that last month, there were 1,047 cases of illegal reentries. Of those cases, 336 individuals had criminal histories, including 67 convictions for violent crime, 107 DUIs, and 119 drug crime convictions.

"If we don't have the cooperation of state and local authorities, some large number of Illegal aliens with a criminal history are going to be walking free on the streets of our community," Bailey said.

"Can you explain what the benefit is or why there is this resistance to actually following the law?" Bruce asked Fox News contributor and Democratic strategist Jessica Tarlov. "And if that is a good political position for the Democrats to be taking?"

"It's a tricky political position," said Tarlov, "as is talking about open borders, for instance. ... Donald Trump actually won the 2016 election because of the immigration issue. It was perceived that Democrats were too weak on immigration."

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"What I think the [Trump] administration needs to emphasize ... is we just can't have you politicizing the process in your state because to get votes or whatever the reason," added Schoen.

"What the attorney general really getting at is that the idea there has to be some measure of uniformity coming from the federal government in an area that's been relegated to federal regulation generally," he concluded. "What he's saying is we can't have all 50 different laws with respect to our borders and the immigration process."

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