At least they agree on something.

At long last, the United States has taken significant and sustained action against Islamist terrorism and piracy in the Red Sea and Gulf of Aden. Donald Trump ordered large-scale strikes against Iranian proxy army Houthis in Yemen this weekend in response to eighteen months of attack on shipping in one of the most heavily used sea lanes in the world. Those strikes continue to today, and Trump vowed they will continue until the Houthis stop attacking international trade -- and warned the Iranians as well:

The Houthi attack on American vessels will not be tolerated. We will use overwhelming lethal force until we have achieved our objective. The Houthis have choked off shipping in one of the most important Waterways of the World, grinding vast swaths of Global Commerce to a halt, and attacking the core principle of Freedom of Navigation upon which International Trade and Commerce depends.

Our brave Warfighters are right now carrying out aerial attacks on the terrorists’ bases, leaders, and missile defenses to protect American shipping, air, and naval assets, and to restore Navigational Freedom. No terrorist force will stop American commercial and naval vessels from freely sailing the Waterways of the World.

To all Houthi terrorists, YOUR TIME IS UP, AND YOUR ATTACKS MUST STOP, STARTING TODAY. IF THEY DON’T, HELL WILL RAIN DOWN UPON YOU LIKE NOTHING YOU HAVE EVER SEEN BEFORE!

To Iran: Support for the Houthi terrorists must end IMMEDIATELY! Do NOT threaten the American People, their President, who has received one of the largest mandates in Presidential History, or Worldwide shipping lanes. If you do, BEWARE, because America will hold you fully accountable and, we won’t be nice about it!

In fact, Trump followed up by making clear that he will hold Iran responsible for any further Houthi attacks:

Let nobody be fooled! The hundreds of attacks being made by Houthi, the sinister mobsters and thugs based in Yemen, who are hated by the Yemeni people, all emanate from, and are created by, IRAN. Any further attack or retaliation by the “Houthis” will be met with great force, and there is no guarantee that that force will stop there. Iran has played “the innocent victim” of rogue terrorists from which they’ve lost control, but they haven’t lost control. They’re dictating every move, giving them the weapons, supplying them with money and highly sophisticated Military equipment, and even, so-called, “Intelligence.” Every shot fired by the Houthis will be looked upon, from this point forward, as being a shot fired from the weapons and leadership of IRAN, and IRAN will be held responsible, and suffer the consequences, and those consequences will be dire!

We'll come back to that in a moment. Reuters reports that the strikes are continuing, and won't end any time soon:

The United States carried out new airstrikes on Yemen on Monday, the Houthis' Al Masirah TV said, expanding the biggest U.S. military operation in the Middle East since President Donald Trump took office in January.

Responding to the Iran-aligned Houthi movement's threats to international shipping, the U.S. launched a new wave of airstrikes on Saturday. On Monday, the Red Sea port city of Hodeidah and Al Jawf governorate north of the capital Sanaa were targeted, Al Masirah said. ...

The strikes, which one U.S. official told Reuters might continue for weeks, come as Washington ramps up sanctions pressure on Iran while trying to bring it to the negotiating table over its nuclear program.

This is the main difference between the response from Joe Biden and his team. Biden would react to attacks on American shipping with one-off reprisals, which did little to dissuade the Houthis from continuing attacks on shipping in international waters. Trump has ordered an extended campaign to degrade Houthi capabilities more decisively, and perhaps even more, to destabilize their grip on Yemen and dislodge the Iranians from their encirclement-strategy gains of the past four-plus decades. 

The Iranians certainly recognize that. They issued their own threats this weekend, although the Iranians probably don't want to put that to the test:

An Iranian general vowed to respond "decisively and destructively" to any threats after President Donald Trump said he ordered American forces to launch military action against Houthis in Yemen.

"We warn our enemies that Iran will respond decisively and destructively if they carry out their threats," Gen. Hossein Salami, the leader of Iran’s Islamic Revolutionary Guard Corps, told state media following U.S. strikes over the weekend against the Tehran-backed terrorist group, according to Reuters. 

"We are not a nation to live in hiding. We are a valid and legitimate system in the world. We announce it if we attack anywhere," Salami was quoted as saying by ABC News. 

No, they most certainly do not. The mullahs of Iran have paid for and control Hezbollah, Hamas, and the Houthis to wage war and encircle the Sunni nations on their behalf, and everyone knows it. The Iranians reportedly have coordinated with the Houthis on shipping attacks with Iranian naval spotters for target selection. Trump expanded his warning to the Iranians in part to make clear that the US will attack all phases of offensive operations against Red Sea/Gulf of Aden shipping. Gone are the days when Iran used proxies to avoid direct consequences for their wars, another new facet of US foreign policy from Trump.

How quickly can Trump get the Iranians to back down -- or, at least get the Iranians to get the Houthis to back down? Probably not too quickly, the WSJ warns. The Houthis have spent a lot of years digging themselves into position and have proven remarkably resilient, likely thanks to the Iranians:

“Freedom of navigation is basic, it’s a core national interest,” Defense Secretary Pete Hegseth told Fox News on Sunday. “The minute the Houthis say, ‘We’ll stop shooting at your ships, we’ll stop shooting at your drones,’ this campaign will end. But until then, it will be unrelenting.”

The Houthis have withstood attacks from internal and foreign enemies throughout their decade in power. The Houthi movement emerged in the 1990s as a ragtag tribal insurgency and seized swaths of northern Yemen, including its capital, San’a, in 2014 sparking a continuing civil war. 

The group sustained thousands of airstrikes by a Saudi-led military campaign over seven years with U.S. backing and failed to restore the internationally-recognized government to power. With Iranian arms and training, the rebels expanded their capacity to menace Saudi Arabia and the United Arab Emirates with drones and missiles. 

After the Gaza war broke out in late 2023, the Houthis turned their sights on Israeli cities and ships passing by the Yemeni coast into the Red Sea, hobbling commerce through one of the world’s busiest commercial waterways. The Biden administration, along with the U.K., responded with intermittent airstrikes that reduced but didn’t stop the Houthi attacks. Israel also conducted its own strikes in Yemen at least four times, including against San’a airport in December.

The question now is whether the U.S. strikes are enough to make the Houthis relent, or up the ante.

Bet on "up the ante" for the foreseeable future -- or maybe just in the short term. At some point, the Houthis are going to lose this capability, and perhaps the Saudis might be interested in containing them even further now that the US has stopped scolding them for action in Yemen. The only real way to end this threat over the long term is to deal with the real authors of all these threats in the region: Tehran. 

Now the question is whether Trump will respond to any 'red line' violations -- and how.