What is DACA and why is it ending?

President Donald Trump on Tuesday sought to blame Democrats for a thorny debate over what to do about a popular immigration program – a program the President and his administration decided to end.

Trump accused Democrats of “doing nothing” for the Deferred Action for Childhood Arrivals system that protected young undocumented immigrants who came to the US as children from deportation.

“Democrats are doing nothing for DACA - just interested in politics. DACA activists and Hispanics will go hard against Dems, will start “falling in love” with Republicans and their President! We are about RESULTS,” Trump tweeted.

Trump’s tweet ignored several facts about the debate, including that the urgency felt in Congress to save DACA was created by his administration’s decision to end the program.

What is DACA?

DACA was an executive action taken by President Barack Obama that allowed undocumented immigrants who came to the US under the age of 16 to apply for protection from deportation. After a background check, those individuals were able to get renewable two-year permits to work and study in the US, as well.

Since it went into effect in 2012, roughly 800,000 people were protected by the program, and roughly 700,000 had active DACA protections in September, when the Trump administration announced its end.

To be eligible, applicants had to have arrived in the US before age 16 and have lived there since June 15, 2007. They could not have been older than 30 when the Department of Homeland Security enacted the policy in 2012.

Why is it ending?

Conservatives have long disliked DACA, with Trump pledging repeatedly during the campaign to immediately rescind it. After he left it untouched during the first half of the year, a group of Republican-led states threatened to challenge the program in the courts in front of a judge who had already blocked an expansion of DACA to parents of those individuals.

Claiming concern that the courts, in the administration’s eyes, would likely immediately invalidate DACA altogether, the Trump administration said the program would be terminated with a six-month window.

One of the biggest complaints from opponents to DACA, besides their argument that it rewarded illegal immigration, was that it was beyond the power of the President and his administration.

Upon ending the program, Trump urged Congress to find a legislative solution and praised recipients as “good, educated and accomplished young people.”

When does it end?

DHS set a date of March 5 for permits to begin expiring. All current permits will be honored until their individual two-year expiration date.

To create that window, DHS offered a one-month window for all DACA holders whose permits expired before March 5 to apply for a renewal.

But more than 20,000 DACA holders who were eligible for the renewal did not get their permits extended, either by not applying and paying the $495 fee or for having the application arrive late. Of the 20,000, at least several hundred may have had their applications lost in the mail, a situation DHS is reviewing in order to allow those applicants to reapply.

What is Congress doing?

Democrats have repeatedly called for Congress to vote on the Dream Act, a bill from Democratic Sen. Dick Durbin and Republican Sen. Lindsey Graham that would essentially turn DACA into a formal legal program and offer those individuals an opportunity to become US citizens over time.

But most Republicans and the President have insisted that any bill to make DACA permanent be paired with border security and other measures to deter illegal immigration.

Trump has pushed for several elements that Democrats have said were nonstarters, including a lengthy list of White House priorities that included changes to asylum, mandatory worker verification and hardline immigration enforcement measures.

He has also repeatedly stated he will not back off a demand for funding his border wall, cutting into family-based migration and ending the diversity visa lottery.

Lawmakers in both chambers have been negotiating heavily over the last few months on how to proceed. Bipartisan talks led by Durbin and Graham in the Senate have made progress, though still remain far from a final deal. In the House, rank-and-file members have sought to bridge their own compromises.

Any bill in the Republican-controlled Congress will need to be a compromise, as Republicans will need Democratic votes to pass an immigration bill that many members of the GOP will refuse to vote for.

Senate Majority Leader Mitch McConnell said he would hold a vote on immigration legislation in January – if a compromise can be reached.

Where do I find out more about DACA?

There are answers to more complex questions on the website of the US Citizenship and Immigration Services.

The Department of Homeland Security has also posted answers to a list of questions about its plans to rescind the program.

CNN’s Catherine E. Shoichet and Susannah Cullinane contributed to this report.