https://x.com/ArmchairW/status/1831176695589618060

Could [the Europeans] reopen the Bab al-Mandeb without US assistance?

After all, right now the Western mission in the Bab al-Mandeb is run by the EU as EUNAVFOR Aspides, so they're already in charge of the area of operations. Reopening the straits will require ground troops to land and occupy enough currently Houthi-held territory to prevent drone and missile launches at maritime traffic transiting the strait. Can the EU muster the force? Power projection requires amphibious assault ships and aircraft carriers. Four European navies operate these capital ships: the UK, France, Italy and Spain. Between them they have four aircraft carriers worth the name (Cavour, Charles de Gaulle, Queen Elizabeth, and Prince of Wales) and eight amphibious assault ships of note (Giuseppe Garibaldi, Juan Carlos I, Galicia, Castilla, Mistral, Tonnere, Dixmude, Albion, and Bulwark). The Italians additionally operate three very small amphibs of the San Giorgio-class. Many of these ships are in some kind of reduced readiness or maintenance status. Realistically the European Union could deploy on a "surge" basis two carriers (with a weaker combined air wing than a single USN carrier) and a single amphibious group comparable to a USN Amphibious Ready Group. This sealift capability would support landing a brigade-size element in Yemen.

The Europeans also maintain a sizable number of airborne formations (Britain, France, Germany, Italy, and Spain all have brigade-plus or -minus elements standing and aren't faced with fighting Russia on short notice), and can field about 100 heavy transport aircraft, mostly A400s. Based on RAND corporation analysis (link in the first post) it would take approximately 105 C-17 sorties to deliver one US infantry brigade with appropriate enablers for a high-end battle. Yemen will be a high-end battle. Although an A400 can jump about the same number of paratroopers as a C-17, it can carry only about half the cargo. Ergo, something like 150 A400 sorties would be required to deliver one brigade, not to mention ongoing sustainment requirements. As it's doubtful more than 30 or so aircraft would be (or even could be, I'm not going to try to analyze ramp space in Djibouti) committed to the operation, the EU task force could realistically only jump a single fully-equipped brigade into Yemen alongside the amphibious landing.

Barring military access from Saudi Arabia or Oman, these two European brigades are going to have to hit the dirt and seize a seaport (perhaps the city of Al Hudaydah, shown) to allow conventional shipping to come in and "administratively" deliver what's going to be a pretty meager follow-on force. That entails a city fight. Even with a seized airport and light reinforcements beyond the initial brigade flowing in by air (alongside much of their logistical requirements!), that's a tall order - particularly given the Houthis have real anti-access/area-denial capabilities and a reasonably competent army. Two or three European brigades in the Middle East, with a mission to seize a major urban area, relying on sketchy air support and tenuous supply lines, can get into a lot of trouble in 2024. Al Hudaydah, for instance, is a Houthi stronghold with a population of close to three-quarters of a million. A smarter course of action may be to enter in non-Houthi controlled eastern Yemen, establish logistics and attack from the east - but it'll be much slower to open the straits and oh, by the way, will require those aforementioned logistics to travel around the Horn of Africa because the Bab al-Mandeb will remain closed in the interim. So the indirect approach is fraught with its own, very significant, issues.

Which brings me to the crux of the problem - Yemen is a big country. It's somewhat larger than Iraq and has about 3/4 the population. The vast majority of that population lives in areas controlled by the Houthis. And, most importantly, the Houthis are very competent fighters. Ergo, even a minimal operation to reopen the Bab al-Mandeb should be expected to be something more on the scale of the 2003 invasion of Iraq than the sort of African bandit-chasing expedition we've seen European forces actually perform in recent memory. And the EU doesn't remotely have the capability to deploy and sustain forces at that level. The force that overthrew Saddam Hussein in 2003 was 200,000-strong - an order of magnitude or more larger than what I've described above.

So to answer my starting question: No. Not a chance. In fact it would be a significant operation even for the United States - certainly not something that could be done quickly, easily, or with the commitment of minimal forces.