Ansar Allah (the actual name for the faction here) fought the 2nd largest arab military on Earth and its international coalition of Arab* countries to a standstill, all while on the brink of a famine. They also have a pretty sizable military in terms of technology, thanks to Iranian supplies of anti ship missiles.
Absolutely astounded that the US is unwilling to dedicate a massive military force to try and meddle with Yemen, especially when the risk to the US is multi-billion dollar warships, and the risk to Ansar Allah is a few anti-ship missile positions, and the continuation of a US-backed war they've largely endured for nearly a decade.
Correction: the US and UK militaries support the Saudis with logistics, training, intelligence, arms sales, and have personnel in the Saudi Coalition command center.
Not direct involvement nor full NATO but still significant support
This is dumb, diplomats have been talking to each other the whole time. Not like they just started asking the Houthis to stop targeting ships, they've been asking the whole time, and will continue to ask for it to stop, even as missiles fly on both sides.