Once again, the left is eating its own.

Democrats are in a good position as they negotiate with President Trump and the congressional majority over their legislative priorities for the next few months: children’s health care, nondefense spending, disaster relief and legalization of the “dreamers,” that group of immigrants brought here illegally as children. They also are within reach of retaking both chambers of Congress in November.

But the dreamers have decided to give the Democrats a rude awakening.

When lawmakers reached a short-term, bipartisan deal last month to keep the government funded, United We Dream, the organization leading the campaign to legalize the dreamers, launched an all-out attack on Democrats for failing to insist that Deferred Action for Childhood Arrivals legislation be included in the spending bill.

The group declared the 17 Senate Democrats who voted for the bill the “Deportation Caucus” and, in a social-media barrage, said they “voted to deport young immigrants.”

United We Dream also fired off a tweet praising conservative Sen. Mike Lee, R-Utah, “for voting NO on a spending bill that did not include a Dream Act.”

This is bonkers.

Democrats – in and out of the supposed “Deportation Caucus” – support legalizing the dreamers. And Lee? His opposition to the spending bill had nothing to do with dreamers. He had called DACA “an illegal abuse of executive power.” Meanwhile, Trump, who created the artificial crisis by announcing he would end DACA, gets away with barely a scratch.

United We Dream deleted the pro-Lee tweet but keeps attacking Democrats. There have been sit-ins and sometimes arrests at Democratic senators’ offices.

The opposition party has been unusually unified over the past year, the result of their common horror over Trump’s ruinous reign. But just as things have begun to look hopeful for Democrats, the “professional left,” as then-White House spokesman Robert Gibbs famously called it in 2010, has begun manufacturing wedge issues to cleave the Trump opposition: single-payer health care, impeachment, abortion and, now, immigration.

I’m sympathetic to the dreamers’ demand for immediate action. Greisa Martinez Rosas, director of advocacy for United We Dream, tells me her group has “called out Trump as a white nationalist” and has identified the many Republicans who oppose DACA as “dream killers.” The group’s recent attacks on Democrats reflect desperation as time runs out for DACA.

The problem for Democrats is that the party is a collection of one-issue entities, which too often use internecine disputes for fundraising and, collectively, thwart any attempt at a cohesive progressive strategy.

The dreamers’ attacks on Democrats are particularly counterproductive because there is no ideological disagreement. Senate Minority Leader Chuck Schumer and other Democrats are playing a chess game: They know Republicans want an increase in defense spending, and they’re seeking to use that as leverage to gain domestic spending increases, renewal of the Children’s Health Insurance Program, disaster relief and DACA legislation.

United We Dream, by contrast, understandably wants the DACA legislation above all. It is demanding that Democrats instigate a government shutdown Jan. 19 by refusing to support a short-term spending bill that doesn’t legalize the dreamers. Those who favor this approach argue that Trump and Republicans would be blamed for the pain of a shutdown, and Republicans would then legalize the dreamers.

Maybe – or maybe the Democrats would be blamed, and their political and legislative hopes (and those of the dreamers) dashed for years.

Instead of training their fire on those who support them, dreamers and their supporters could use their prodigious energy on the 34 House Republicans who said they support legalization. These Republicans could force House Speaker Paul Ryan to include DACA in the spending bill. Also Tuesday, a federal judge ordered that the DACA protections remain in place while a court case proceeds. And Ryan softened his earlier insistence that DACA not be considered as part of a spending bill.

Meanwhile, dreamers and the Democrats will likely gain more leverage against Trump and the Republicans with the approach of March 5, the day the DACA program, per Trump’s order, is set to expire. Trump, who had made clear he has no appetite for deporting the dreamers, would then have to capitulate – and Democrats could get a better deal for the dreamers.

Patience has been paying off for the Democrats. In his marathon televised session with lawmakers at the White House on Tuesday, Trump softened his position on the border wall and suggested a DACA deal could be had while postponing thornier issues such as chain migration.

Dreamers will win this fight – if they don’t mow down their friends first.

Dana Milbank is a columnist for The Washington Post. He can be contacted at:

dana.milbank@washpost.com

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