“Mi casa es tu casa,” contra Eric Adams, is not an immigration policy.

Not for New York — and not for the nation.

Adams last week offered up Gracie Mansion as a hostel for border-hoppers — right after he suggested that ordinary New Yorkers open their own homes.

It was a slightly insane proposal, and he quickly backed away from the Gracie gambit.

But it underscored hizzoner’s “Who, me?” approach to the migrant crisis — with its budget-crushing costs and socially destabilizing potential.

Adams is never at a loss for dramatic — if often empty — gestures.

Opening Gracie wouldn’t work for “legal reasons,” he backtracked, but never mind.

“I think leading the challenge of the migrant problem is both substantive and symbolic,” he declared — adding “as I always say, good generals lead from the front.”

Heh.

That’s our modest mayor.

But Adams certainly is correct about the symbolism: Offering to turn your spare bedroom over to illegal immigrants doesn’t do anything for “the migrant problem” — it just makes your city a migrant magnet.

As for good leadership — well, not so much.

Obviously not from City Hall — but most especially not from New York’s power-packed congressional delegation.

Really, when the two most powerful Democrats in Congress — Senate Majority Leader Chuck Schumer and House Minority Leader Hakeem Jeffries — hail from Brooklyn, you’d think city would be better treated.

You would be wrong.

All Gotham gets from those two is pious blather and an occasional, wholly inadequate pot of federal crisis cash.

Remember when all politics was local?

No more.

Now all politics is self-serving, partisan hackery.

No reasonable person believes there are easy solutions here.

Economic migration is a global phenomenon — yet if there is a lesson to be taken from the past decade, it’s that ignoring the problem just makes it worse.

And that’s the Biden approach.

The administration chooses to define it away — piping phony stats to claim progress while uncountable thousands cross the border illegally every year.

Schumer and Jeffries are too frightened of Biden to say boo (also Kathy Hochul, don’t forget her.)

And the one time Adams dared complained about the White House, he got his hand slapped hard.

He’s been quiet since.

Nevertheless, the mayor stands in a bullseye.

An unsustainable number of Biden’s border-hoppers head straight to New York — 13,000 were processed through the Roosevelt Hotel reception center over the past month, and 2,000 just last week.

Not to be flip, even if Hizzoner were to house them in every corner of Gracie Mansion, there would be more arrivals in the morning. And more, the day after.

Billions have already been spent, and billion more will be necessary; the current tab runs to $8 million a day. Pretty soon that well will be dry too.

So let’s pretend no longer works; General Adams truly is at the front, and now it’s time for him to lead — to speak loud truth to self-serving power.

Email: bob@bobmcmanus.nyc