President Joe Biden is headed to the Middle East to show solidarity with Israel, but he should use the occasion to do something even more vital: prove that he understands the region’s woes now stem largely from the regime in Iran — and announce major plans to hold it accountable.

What kind of plans?

For starters, Biden should immediately end all further nuclear talks and reimpose the toughest possible sanctions on Tehran.

As it stands, his sanctions relief has allowed Tehran to move from just $4 billion in available global reserves when Biden took office to over $40 billion today.

Step 1: Officially re-freeze the $6 billion he released in his now demonstrably misguided ransom payment for US hostages.

Step 2: Drop the delusional efforts to pretend Iran’s rulers didn’t collude in and sign off on the 10/7 terror assault, the worst atrocities against Jews since the Holocaust.

Step 3: Answer Iran’s latest outrageous threats, like Foreign Minister Hossein Amirabdollahian’s Monday talk of “preemptive action” against Israel, with powerful ones of his own.

For example, vow to retaliate against its proxies, and perhaps strike Tehran’s nuclear facilities, if Hezbollah, any Iranian-backed militias or Iran’s own Revolutionary Guard launch any new attacks.

That’s the best way to deter escalation of the war beyond Gaza.

(By the way, Amirabdollahian’s threat essentially admitted Iran calls the shots: How else could Tehran unleash the “resistance”?)

Surely, at the very least, Biden needs to call out the mullahs as the sick puppeteers they are, pulling the strings of their proxy attack dogs: Hamas, Hezbollah and assorted militias.

If, instead, Biden again displays his signature weakness, he’ll lead the United States into an Iranian trap: Images of Gazans, Israeli soldiers and hostages (including Americans) being killed will feed domestic calls for appeasement, stoke dissent and division — and invite more Iranian-directed aggression.

The consequences go beyond the Middle East: Russia and China are now allied with Iran on multiple levels: Tehran supplies weapons to Moscow for its brutal, criminal war against Ukraine and supplies ever-more oil to Beijing.

All three are looking to knock back America and break up civilized alliances (in Europe and Asia) that restrict their ambitions.

All that makes this moment absolutely critical for America.

Biden’s actions — or lack thereof — will shape the future not only of the region but the world.

The only question now is: Does he have the courage, wisdom and backbone to meet this monumental challenge?