President Obama is reportedly pondering proposals that would effectively grant amnesty to millions of illegal aliens, above and beyond the potentially 1.4 million who gained amnesty in 2012. Supporters of executive action dispute the use of the word “amnesty,” but not the substance of it. Whatever you call it, an enormous number of people who had no right to live and work in the United States in October may acquire that right in December, by a single act of presidential power.

At an event in Little Rock this weekend, former President Bill Clinton explicated the motive for action. His own words were more cautious and periphrastic, but a Politico headline bluntly abbreviated his logic: “Clinton: No Obama immigration action may have hurt in midterms.” If not acting in 2014 cost the Democratic Party the Senate, not acting before 2016 may cost Clinton’s wife the presidency—or so he seems to fear.

Yet it’s curious that if executive immigration action is so politically popular, Clinton is so ready to leave the credit to the current occupant of the White House rather than to the next. In fact, even from the point of view of the Democratic Party and the Obama administration, the reported policy is fraught with danger—for the country, but also for the president and his party. Here are five reasons for the president not to proceed with his reported plan.

1) The reported immigration plan makes a liar of the president. Obama has repeatedly pleaded for relief for those young people “were brought to this country by their parents, sometimes even as infants, and often have no idea that they’re undocumented until they apply for a job or a driver’s license or a college scholarship.” The implicit message: Don’t visit the sins of the parents upon the blameless children. The actual policy, however, exempts the parents as well.

The actual action will cast an ugly afterglow of deception on the case the president has argued over six years, which drew a distinction between conscious and inadvertent lawbreakers.

2) The reported immigration plan invites new surges of illegal immigration. Advocates deny it, but would-be illegal immigrants do respond to perceived changes in U.S. enforcement policy. Remember, the president suspended enforcement action against so-called Dreamers in June 2012. Within three months 150,000 further Central American teenagers and families surged across the border. A sharp application of enforcement since September has slowed the rush. Many would-be illegal immigrants are not desperate refugees. They respond to opportunities. They new executive action opens a new opportunity. The age to qualify as a “child” will be raised from 12, the age used in 2012, to 16. Eligibility for amnesty will be extended from those who entered before 2007 to those who entered before 2010.

3) The president’s reported plan would legalize as permanent U.S. residents many thousands of criminal aliens. Reportedly, the president’s next amnesty will exclude aliens with “serious” criminal records. But the Obama administration defines serious criminality much more permissively than many other Americans would. Case in point: In 2013, the administration released more than 36,000 illegal aliens arrested for various forms of lawbreaking. The administration decided these 36,000 had not done anything sufficiently serious to merit deportation proceedings. What had they done? The Center for Immigration Studies reported:

Among them, the 36,007 had nearly 88,000 convictions, including:

  • 193 homicide convictions (including one willful killing of a public official with gun)
  • 426 sexual assault convictions
  • 303 kidnapping convictions
  • 1,075 aggravated assault convictions
  • 1,160 stolen vehicle convictions
  • 9,187 dangerous drug convictions
  • 16,070 drunk or drugged driving convictions
  • 303 flight escape convictions

It’s reasonable to fear that the 2.5 million or 4 million or 5 million people who will gain residency rights under the next round of presidential action will include tens of thousands more such criminals.

4) The president’s plan would be costly. The vast majority of those who would gain residency rights under the president’s reported action will be poor. Their low incomes will qualify them for means-tested social programs just as soon as their paperwork is in order. This will not be a small-dollar item. Forty-one percent of the net growth in the Medicaid population between 2011 and 2013 was made up of immigrants and their children. Legalize millions more poor immigrants, and sooner or later, programs from Medicaid to Section 8 housing vouchers to food stamps will grow proportionately. It’s not widely appreciated how much past immigration choices contribute to present-day social spending. In 1979, people living in immigrant households were 28 percent more likely to be poor than the native-born. By 1997, persons in immigrant households were 82 percent more likely to be poor than the native-born. Wittingly or not, U.S. immigration policy has hugely multiplied the number of poor people living in the United States. The president’s plan will put millions of them on the path to qualifying for welfare benefits.

5) The president’s plan will convulse national politics. Obama is planning to use his immigration-enforcement power in a way never before seen in U.S. politics. It may technically be legal, but it rips up accepted norms of presidential conduct. It’s farcical to describe what the president is considering as an act of “prosecutorial discretion.” For all practical purposes, it’s legal nullification on a mass scale: not an interpretation or enlargement of congressional purpose, but a flagrant defiance of congressional purpose. “Congress wouldn’t change the law the way I wanted, so I had to void the law” is not an excuse or justification. Presidents are expected faithfully to execute even the laws they don’t like. The shock to the political system will be intensified because the president’s political opponents almost unanimously believe that his act of nullification is motivated by the crassest kind of political calculation, a belief amply supported by the words of fellow Democrats from Clinton on down.

Admittedly, the Republicans have themselves walked up to the edge of the precipice of illegitimacy more than once during the past six years. Twice they nearly pushed the country into a default on its obligations. The operative words here, however, are “edge” and “nearly.” Obama is considering actually jumping over that edge into what so mild a critic as Ross Douthat has dubbed “Caesarism," “caudillismo,” and a “betrayal of our political order.” What comes next won’t be deadlock. It’ll be unrestricted political warfare between a badly weakened president and a Congress that will regard him as a political outlaw and constitutional desperado.

It’s not too late. Don’t do it.