In hailing an emerging bipartisan consensus in the Senate on immigration reform, President Barack Obama added Tuesday to the momentum to fix a broken-down system that long ago stopped making sense and serving the country. For at least a day, Washington found itself in the glow of a rare — and welcome — harmony.

It’s not likely to last, as Obama acknowledged in a speech in Las Vegas, where he laid out a framework for overhauling the immigration system. But the president did the sensible thing by standing aside, for the time being, to let Congress take the lead on crafting a bill in the coming months.

The president’s strategy appears to be to allow Senate Republican leaders, including the four who signed a bipartisan blueprint on immigration Monday, to soften up the deep, long-standing animosity among House Republicans toward granting legal status to illegal immigrants. That makes sense in Washington’s polarized political atmosphere, where legislation from the White House may actually stiffen the GOP’s resistance.

But Obama also made clear that if progress slows toward a deal, the administration will submit its own bill. The implication, and the threat to Republicans, is clear: Act soon to forge a reasonable deal, or risk being seen — once again — as impeding progress on the issue that will shape political attitudes for the nation’s fastest-growing group of minority voters.

Congressional Republicans, especially in the House, have trashed the idea of “amnesty” for illegal immigrants for years. They should think hard about the carrot, as well as the stick, the president is offering them in the aftermath of November’s elections, in which he won more than 70 percent of the Hispanic vote. It may not erase all the GOP’s woes with Hispanic voters if the party goes along with a plan that includes a path to citizenship for undocumented residents. But blocking a deal will almost certainly cement those problems for a generation or more.

Congress must find a way to clear the nation’s current waiting list for permanent-resident visas, which now includes applicants who have been waiting for nearly 25 years. It makes no sense to require illegal immigrants to wait at the back of a line that may exceed their life expectancy.

And while Republicans may reasonably insist on measures to tighten security at the border — which is already more secure than at any point in recent decades — they should not be allowed to use it as an excuse to further delay sweeping reform.

The president has offered a useful roadmap — even tighter border security; tougher requirements for employers to verify applicants’ immigration status; and a pathway to citizenship — that closely mirrors the bipartisan accord taking shape in the Senate. The real test will be whether lawmakers can nail down the details of a bill that recognizes the reality that 11 million undocumented immigrants are here to stay, as well as the nation’s ongoing need for new immigrants who bring energy, drive and talent to our shores.

The Washington Post (Jan. 30)