States
The Houthi movement (Ansar Allah) controls most of northern Yemen including the capital Sanaa and exercises sovereign-like functions there. Houthi maritime operations in the Red Sea and Bab el-Mandeb directly shape global shipping costs and route choices. The movement's alignment with Iran is real but its operational decisions are its own; framing it as a simple proxy understates its agency.
Sustained ground campaign into Houthi heartland
Has historically failed and produced retaliation against Gulf infrastructure.