After weeks of threats, Yemen's Houthis have entered the war, launching attacks against Israel in support of Iran. The group are now threatening military action in the Red Sea if t

After weeks of threats, Yemen's Houthis have entered the war, launching attacks against Israel in support of Iran. The group are now threatening military action in the Red Sea if the waterway is used by the US and Israel to attack Iran. Al Jazeera’s Julide Ayger explains.