Former Florida Gov. Jeb Bush, usually a key Republican voice on immigration issues, has been conspicuously silent with regard to the plight of thousands of unaccompanied children from violence-wracked countries in Central America crossing the Southern border illegally. Last night, though, he jumped into the debate, calling for various steps to be taken to address the crisis and delivering a stern warning to his fellow Republicans.

“President Obama has promised to once again act unilaterally if Congress fails to take up immigration reform,” he said in a Wall Street Journal op-ed co-written with Clint Bolick, a vice president with the Goldwater Institute and the co-author, with Bush, of a 2013 book on immigration reform.

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“Now is the time for House Republicans to demonstrate leadership on this issue. Congress should not use the present crisis as an excuse to defer comprehensive immigration reform. Whether President Obama is making health-care policy by fiat or using the Environmental Protection Agency to circumvent the lawmaking process, we have too often seen what happens when the president oversteps his constitutional authority. Avoiding similar disastrous results will require legislative action by both parties.”

Bush took fire from the Republican base earlier this year for making the point that many illegal immigrants cross the border as “an act of love” in order to provide better lives for their families. This time around, he leveled plenty of criticism at the Obama administration, saying, “[H]e has failed to call for a change in the law, to engage across party lines or to take sufficient steps to keep more children from coming.”

While conceding that these children “are trying to escape horrific gang violence and dire conditions in their native countries,” Bush appeared to endorse a proposal put forward by Arizona Republican Senators John McCain and Jeff Flake, among others, which would make deporting children from Honduras, El Salvador, and other Central American countries easier and faster.

“Except for those deserving few who may demonstrate true cause for asylum or protection from sex trafficking, these children must be returned to their homes in Central America,” he wrote.

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Bush’s re-entry into the immigration discussion comes as a Quinnipiac poll shows his political star dimming somewhat, even in his home state of Florida. The results, released Thursday morning not only show Bush losing to likely Democratic nominee Hillary Clinton by a margin of 49-42 percent, but also show him losing ground against other Republicans, including a surging Sen. Marco Rubio.

In May, 27 percent of voters polled by Quinnipiac picked Bush as their favorite from a field of potential Republican candidates. Kentucky Sen. Rand Paul ran second with 14 percent, and Rubio third with 11 percent.

Just two months later, Bush’s numbers had fallen to 21 percent, while Rubio jumped to 18 percent. Texas Sen. Ted Cruz earned 10 percent, while Paul dropped to 8 percent.

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