It’s time (past time!) for Mayor Eric Adams to at last full-on challenge the so-called right to shelter, not just plead for some temporary limits.

The migrant crisis is the obvious spur for that action, but it’s really just exposed the fundamental madness of the “right” — which is based solely on a consent decree agreed to by Mayor Ed Koch more than four decades ago, plus a series of court rulings that have turned sheltering anyone who requests it into a $2-billion-a-year City Hall obligation.

Adams only went to court seeking short-term relief specifically for the illegal migrants who’ve flooded into town, and the court has sidelined that into mediation talks with ideologues committed to keeping the “right” unlimited.

This, as The New York Times has deigned to report out the obvious: “Many migrants entering the U.S. southern border have been steered to New York City by relatives, politicians and smugglers, in part because of the city’s right-to-shelter policy.”

And as Gov. Kathy Hochul is looking to reduce the state’s migrant spending (most of which has gone to the city) as her budget director calls it “unsustainable.”

If Albany’s outlays are unsustainable, what does that make the city’s far higher spending?

And while the “asylum seekers” present an unusually large challenge, how much of the city’s “normal” homeless population has been drawn here by the legal guarantees?

Heck, the city would surely care for most homeless even without the “right” — but could do so far more rationally than without the insane micromanagement (and need to litigate even modest reforms like setting minimum behavior standards for shelters) that the consent decree has led to.

As it stands, City Hall is end-running the right now when it comes to migrants, forcing them to reapply after 30 days in a shelter (60 for migrant families), and giving them a bureaucratic runaround when they try to sign up again.

But as long as the core “right” remains unchallenged, that only guarantees the advocates will seek — and get — court orders forcing the city to quit those games, as Nicole Gelinas noted in Monday’s Post.

Again: Adams himself warns that housing unlimited migrants will “destroy the city.”

It already threatens funding for schools, garbage collection, public health and other social services.

And, again, the vast amounts spent on normal homeless already consume major public resources that no other municipality in the country is obliged to spend.

The “right” doesn’t even apply anywhere else in New York, even though it’s supposedly based on the state Constitution.

End this farce, and let the city balance caring for the homeless with all its other social goals.