[maxglute]

Iran has access to Persian Gulf. Houthis has access to Red Sea. Together that overseas SLOCs for about 30% of global oil and LNG, both their shipping, and with sufficiently advanced (read not very) missiles, their infra - see Yemen attacks on Saudi refineries. By acquiring theatre range missiles that can actually hit things, they created credible regional power projection capablities, and hence leverage to threaten global energy, which limits what US can do against them since much of it goes to their partners.