have fired missiles and other projectiles at commercial ships, as well as a number of us owned merchant vessels. the attacks have disrupted global trade and stirred fears of a further destabilised middle east. the us has carried out eight operations on its own against the houthi movement in the past two weeks. monday s strikes mark the second joint action by the us and uk in yemen, the first, back onjanuary 11. the bbc s defence correspondent jonathan beale gave us his analysis. it would have been a lot more intelligence used like the first time a co ordinated attempt to try to degrade at least their ability to do this. the trouble is the houthis show no sign of backing down, a determined group have been writing the saudis. the us and the uk have been involved in this action, no other country has and i think that is because they do not know what the end game is here. this tip could go on for weeks. this tit for tat. the houthi movement says its attacks on red sea shipping