Perhaps I’m missing something, but I don’t see the compelling US interest here. “Compelling” in terms of being compelling enough to get dragged into what could end up being a pretty broad war.
Not to specifically endorse the Houthis, but the fact is that - much like in the case of Syria - you need to look at the Houthis in the context of all the other major players in that country, some of whom are just as bad or worse, e.g. al-Qaeda of Yemen.
I apreciate that the US doesn’t like the Houthis’ links to Iran, but that hardly seems like a legitimate reason to get involved in a war, especially given reports that Wikileaks revealed US skepticism over the extent of Iranian links to the Houthis (see e.g. https://wikileaks.org/plusd/cables/09SANAA2186_a.html#efmAjaAmV).
What I’m wondering is whether this is mostly an attempt to curry favor with the Saudis, who are really worked up about Iran and feel betrayed by the US nuclear negotiations with Iran, and perhaps this is an attempt to balance things out and reassure them by offering some limited support in their battle against what they see as Iranian proxies.
But perhaps I’m missing something.