It seems as if President Biden’s erroneous Iran policies are starting to change in reaction to the Islamic Republic’s malign role in the Mideast, made clear by the carnage in Israel’s south. If so, the time has come for a complete U-turn, rather than tweaks at the edges.

Appeasing the ayatollahs is no longer — if it ever was — an option. America’s role on the world’s stage now depends on ending, or at least significantly defanging, the regime that strives to control the Mideast and beyond. The initial task is to deter Iran’s proxies.

Will Tehran and its proxy armies heed Washington’s warnings, or will they dismiss them as a mere followup to the red line President Obama failed to enforce in Syria or Mr. Biden’s incompetence in executing the Afghanistan evacuation?

Administration officials, for now, seem to be twisting themselves into pretzels as they attempt, at least partially, to minimize the Islamic Republic’s direct role in Hamas’s murderous attack on Israeli civilians.

“Did they have foreknowledge? Did they help plan the attack? There’s no evidence of that at this point,” Mr. Biden said Sunday on CBS’s “60 Minutes.” As he spoke, the Iranian foreign minister, Hossein Amirabdollahian, was touring the region, conferring with officials of Hezbollah and Hamas.  

Mr. Biden’s elusive “evidence,” meanwhile, can be found on newspapers’ front pages. Following up on a report in the Wall Street Journal, the New York Times on Friday reported, based on regional sources, that “officials from Iran and Hezbollah helped plan the attack.”

The Sun also reported on Iran’s role in all stages of the attack, from defining the goals of the Hamas atrocities in Israel’s south to the final approval. Also, administration officials acknowledge that Iran arms, finances, and trains Hamas. “Iran constantly supports Hamas and Hezbollah,” Mr. Biden said in the “60 Minutes” interview.

So, why the equivocation? The answer may be more tactical than strategic, as Israel is preparing for a complex, deadly land war in Gaza that is likely to be lengthy. Confronting another Iranian proxy, Hezbollah, at the same time would make the Gaza war much more challenging.

Although counterfactual, America and Israel hope that partially exonerating Tehran for the October 7 massacre would convince Iranian policymakers to hold back their Hezbollah proxy. 

“President Biden told you in English, ‘Don’t do it,’ and I am telling you in Hebrew, ‘Watch out,’” Prime Minister Netanyahu warned Hezbollah on Monday, saying that Israel’s response to past attacks would pale in comparison to the destruction in Lebanon if it joins the current war. 

America is emphatic that it too intends to act. The USS Dwight D. Eisenhower’s Carrier Strike Group is on its way to join the Gerald Ford group in the eastern Mediterranean. 

At one point, likely soon, Israel will have to address the existential threat posed by Hezbollah. For now, though, it needs to first deal with Hamas. Rather than challenging the Islamic Republic’s entire gamut of Mideast proxy armies at once, Jerusalem and Washington are sending a subtle message to Tehran.

The idea is to convince the Iranians to “lose one pawn on the chessboard,” the vice president at the Foundation for Defense of Democracies, Jonathan Schanzer, tells the Sun: Although the IRGC has spent billions of dollars on building up Hamas, it would rather lose it if the rest of Iran’s power structure is spared. 

With that message in mind, telling the mullahs that America has doubts about its full complicity in the Hamas atrocities makes sense. Yet, are the Islamic Republic and Hezbollah buying it? 

Mr. Biden has spent the first half of his term as president trying to buy off Iran. From failed attempts at reviving the moribund nuclear deal to the unprecedented $6 billion ransom for five American hostages, his policies have been an abject strategic failure.

Now, they are becoming a political liability as well. Mr. Biden’s Iran envoy, Robert Malley, is under investigation for sharing America’s secrets with unauthorized persons. A Tehran-run influence network that includes administration officials has recently been exposed.

Partially confirming Iran’s malign activity, suspending Mr. Malley, and reports that Washington is halting payment on the $6 billions ransom indicate that Mr. Biden is beginning to reverse course.  

Yet, even as America sends significant firepower to the region, Hezbollah is escalating its assault on Israel, including daily mortar attacks on the north and its terrorists’ attempts to infiltrate the border. 

Israel is doing its utmost to leave such local skirmishes at low intensity. Yet, a large number of Israeli casualties would trigger a full-scale war. If Mr. Biden fails to respond militarily after repeatedly saying “don’t,” no future American warnings would be taken seriously by its enemies.