Maybe the Houthis need something to make them more unpopular, keep their friends and advisors away.
Something that can stop them associating, damage civil organisation, destabilise their military tribal leadership and need assistance from the outside world. Something to refocus their energies.
Something deniable.
Something stealthy.
Remember when we had that COVID thing ?
(I’m not serious, it’s too evil, but it makes one think)