President Joe Biden declared Yemens Houthi rebels a “terrorist” organization on Friday, hours after the US military launched retaliatory strikes across Yemen with Britain. Biden warned Washington would act again if the Iran-backed fighters persist with attacks in the Red Sea region, calling their behavior outrageous.The rare strikes overnight targeted Houthi military infrastructure and supply lines. They represent an escalation by the US and allies to counter months of assaults on shipping by the militants near the strategic Bab al-Mandab strait. Houthi aggression has forced vessels to take longer alternative routes since October. Houthis are terrorist: Joe Biden “I think they are,” remarked Biden when asked if he considered the rebel group terrorists.“We will ensure we respond to the Houthis if they continue this outrageous behavior along with our allies.”Earlier, the White House affirmed the US sought to avoid full war in Yemen but would not hesitate to employ further force. The UK Foreign Office dubbed recent Houthi actions “unacceptable”. Why are Houthis launching attacks in the Red SeaThe Houthis, an Iran-backed rebel group had the majority of Yemen under its control over the decade. In their efforts to show solidarity with the Palestinians suffering in Gaza under the continuous attacks of Israel, this rebel group have come forward with arms and ammunition to block the Red Sea transit- one of the worlds busiest trade lanes Tensions soared in Gaza after an October 7 attack by Hamas killed 1200 Israelis per Tel Aviv.Israels subsequent bombardment has eradicated over 23,000 Gazans so far, around 1% of the cramped coastal enclaves population, said Gaza health officials.The Gaza crisis has spiralled into violence elsewhere in the Middle East. Houthi aggression expanding into vital shipping channels prompted a joint American-British demonstration of resolve overnight. Further disruption risks global supply chainsThe vital Bab al-Mandab straits are used for trade between Europe, Asia and Africa worth billions daily. Continued assaults or extended shipping avoidance of the area might have severe economic consequences.Oil prices briefly spiked 3% Friday, underscoring potential implications. “It could potentially have quite significant consequences on global growth,” Maersk CEO Vincent Clerc said.The Houthi insurgency overrunning Yemen from 2014 prompted Saudi-led intervention in 2015 and years of inconclusive conflict. Biden and other Western leaders are under pressure to help end the crisis enabling instability and humanitarian disasters.