Jeh Johnson, President Barack Obama's secretary of homeland security, warned his fellow Democrats not to shift too leftward on the issue of immigration.

Johnson acknowledged most Americans want to help immigrants who are truly in need, but "when we talk about deprioritizing the deportation of those apprehended at the border or decriminalizing illegal immigration ... That just simply incentives more illegal immigration. We lose control of our borders."

"In the same vein, by taking a formal step of decriminalizing illegal immigration, what we’re saying as a country and as a society is we’re prepared to see a lot more of this. When you decriminalize something, it's because society is prepared to see that behavior, perhaps regularly but en masse, and I don’t think that’s where the American people are. I’m a Democrat, I’m a loyal Democrat, and I want to see us win in 2020, but to do that, we’ve got to appeal to the wide consensus out there on immigration and a lot of other issues," he told Morning Joe on Wednesday.

Johnson said his opposition to Democratic proposals does not mean he endorses President Trump's hard-line stance on immigration, but he wants to warn the 2020 Democratic candidates.

Johnson, who served as secretary of homeland security from 2013 to the end of Obama's presidency in 2017, has previously stated that decriminalizing border crossings is "tantamount to declaring publicly that we have open borders." He also said putting immigrants in "chain link barriers, partitions, fences, cages, whatever you want to call them" did not start when Trump became president.

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