Deluged with bad news on numerous fronts—especially from the poorly executed rollout of his signature achievement, Obamacare—the president wants Congress to turn its attention to immigration reform.

But President Obama is finding his “comprehensive” approach to immigration to be a much harder sell in the wake of the Obamacare debacle.  Not only are people more doubtful of grandiose “comprehensive” plans hatched in Washington, they are newly distrustful of promises made by those pushing such solutions.

In June, before the Obamacare rollout imploded, the Senate passed a shambles of a bill centered on granting amnesty—euphemistically termed “a pathway to citizenship”—to 10 million or more illegal immigrants. The House of Representatives was not eager then to follow the Senate’s lead toward one huge bill, and is even less inclined to do so now.

Instead, House Speaker John Boehner thus far has opted for a step-by-step approach that examines specific problems and challenges in our complex, oft-unenforced immigration system. Given the Obama administration’s evident willingness to make false assurances—before and after passage of comprehensive legislation it seeks—House conservatives are understandably reluctant to trust the president to keep the promises he makes about fixing and enforcing immigration law.

Such doubts are reinforced by the administration’s own actions—and inactions.  In just the last few weeks came the news that deportation of unlawful residents is at the lowest level in 40 years. Also making headlines: the fact that the Department of Homeland Security cleared 81 percent of 580,000 young applicants for provisional legal status, a process initiated not by Congress but the by the administration.

It’s not just the current administration that has a poor track record on enforcement. The 1986 amnesty for 3 million illegal immigrants was part of a similarly “comprehensive” bill that contained provisions for enhanced border security and apprehension of future violators of the law.  But many such provisions went unfunded and unenforced.

According to the Congressional Budget Office, the Senate-passed bill still would open the door to millions of new illegal immigrants. It wouldn’t be the amnesty to end all amnesties any more than the 1986 deal, which also promised to be just that.

Under the Senate’s amnesty-centric fix, the Obama administration could be expected to pick and choose what it enforces. Waiting periods for full citizenship, for example.

To attract conservatives’ support, the Senate bill ramps up spending on Border Patrol staff and related security measures. But it also grants extensive authority to the secretary of the Department of Homeland Security to waive such provisions. So if you liked the border security promised by the bill, you won’t necessarily get to keep it.

Even without the sad precedent of Washington’s one-size-fits-all prescription for health care, Americans are right to be wary of House passage of any piece of the immigration puzzle. A subsequent deal with the Senate could well result in amnesty for millions of people who broke our laws in coming or staying here.

Sen. Robert Menendez (D- N.J.), one of the president’s closest allies in the Senate, recently gave the game with the House away. “Get us to conference,” Menendez said. “In a conference, we can negotiate the notion of bringing all those bills together.”

Such anticipation from amnesty advocates prompted Rep. Michael McCaul (R-Texas), sponsor of a bipartisan border-security bill, to draw a line Oct. 30 on a national radio talk show.

“I am not gonna go down the road of conferencing with the Senate bill,” said McCaul, chairman of the Committee on Homeland Security. “And I told Boehner that he needs to stand up and make that very clear, that we are not going to conference with the Senate on this.”

McCaul is among a growing number of House lawmakers who understand that the Senate’s all-or-nothing approach would harm taxpayers. It would disregard the rule of law, cost trillions in benefits and services for those who get amnesty, and fail to guarantee enforcement of laws already on the books. Finally, it would be unfair to those who have obeyed the law by waiting in line.

To build the trust of the American people, immigration reform should be a step-by-step process that begins with securing the border and enforcing existing laws.

Unfortunately, President Obama has not demonstrated he can be trusted to do the hard work of either -- no matter how many more laws Congress passes.

 - Derrick Morgan is vice president for domestic and economic policy at The Heritage Foundation. Ken McIntyre is Heritage’s Guardabassi fellow in media and public policy studies.