If Congress won’t do its job, the Supreme Court can’t do its job.

That’s been the warning since the Republican-controlled Senate made it clear in March it won’t even consider filling a vacancy on the Court while Barack Obama is president — and that damage has come in no time at all.

EDITORIAL

On Thursday, the short-handed Court, stuck in a 4-4 tie, was unable to deliver a definitive ruling in one of the most pressing issues facing our nation, whether to grant temporary protections against deportation to more than 4 million undocumented immigrants so that they can live stable and productive lives.

The Court’s failure to decide means the two programs, created by Obama by executive order, will remain blocked from going into effect, in keeping with a lower court ruling. But because the question of the programs’ constitutionality remains unresolved, an inhumane legal limbo for undocumented immigrants continues on. Try building a solid life on that.

In the short run, supporters of Obama’s efforts to allow undocumented workers to come out of the shadows — to work, go to school, get a driver’s license and the like without fear of arrest — arguably dodged a bullet. Had Justice Antonin Scalia, who died in February, still been on the Court it almost certainly would have ruled Obama’s executive actions were not constitutional.

But there is no resolution in that. There is no firm ground. There is no map suggesting what policies or strategies the president and Congress should pursue next. A broken immigration system remains broken.

“For more than two decades now our immigration system, everybody acknowledges, has been broken,” Obama said Thursday. “And the fact that the Supreme Court wasn’t able to issue a decision today doesn’t just set the system back even further, it takes us further from the country we aspire to be.”

Our Constitution provides for three branches of government — the executive, the legislative and the judicial. But what we’ve got in practice, so long as an evenly divided high court is unable to rule on key constitutional issues, is about 2 1/2 branches of government. The weakened court risks becoming a junior partner. Raw partisan politics, played out between the president and Congress, immediately become less checked by higher principles.

The minute Senate Republicans announced they would not even consider the credentials of Obama’s nominee to the Court, Judge Merrick Garland, they guaranteed that filling this vacancy — and every future vacancy — would be politicized to the extreme.

There is no reason to believe this cheap politicization — litmus tests before  qualifications — won’t continue even after the November presidential election. No matter who is elected.

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