The White House’s National Security spokesperson John Kirby had told reporters today that he wouldn’t "telegraph [America's] punches" from the podium. But the fact that an emergency Cabinet meeting had been called in London must have given some pretty big clues to the Houthis about what was coming. Even with this none too subtle hint, the scale and scope of the strikes may have still come as a surprise in both Sanaa and Tehran.
US president Joe Biden was clear in his written statement issued immediately after the attacks.
"These targeted strikes are a clear message that the United States and our partners will not tolerate attacks on our personnel or allow hostile actors to imperil freedom of navigation in one of the world’s most critical commercial routes", he said.
"I will not hesitate to direct further measures to protect our people and the free flow of international commerce as necessary", Biden added.
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This is the first time Houthi rebels backed by Iran have been hit by US and British forces. It came after repeated warnings from both the White House and Downing Street that attacks on international shipping could not be tolerated any longer.
Then, today, the Pentagon spokesman Brigadier General Patrick Ryder confirmed another missile had been launched from the Yemen coast at a ship, thankfully missing its target. It was the 27th such incident in less than two weeks. It followed a barrage of 21 drones and missiles fired on Tuesday, forcing HMS Diamond, a Royal Navy type 42 Frigate to launch Sea Viper missiles to neutralise the threat.
A senior administration official said to ITV News and other media outlets immediately following the strikes that the Houthis "with Iranian support" have targeted over 20 missiles and ballistic missiles crossed the Red Sea.
"At least three ships have been hit, and we've been, we've had extremely close calls, such as a ship, as I had mentioned, carrying US owned jet fuel that the Houthis targeted last month", the US official added.
“The Houthis claim that there are attacks on military and civilian vessels are somehow tied to the ongoing conflict in Gaza that is completely baseless and illegitimate.
"[They] also planned to be targeting specifically Israeli-owned, ships or ships bound for Israel. That is simply not true. They are firing indiscriminately on vessels with global ties.
"Most of the ships that have come under attack have nothing whatsoever to do with Israel, and even if they were that, even if that were not the case, it is no justification for these illegal attacks in international waterways."
In a speech on Thursday (11th January), the Houthi leader Abdul Malek Al-Houthi said that any US attack on Yemen "will not go unanswered", warning that the response will be "much more" than attacking US ships in the sea.
It raises concerns that the action will escalate simmering tensions in the region. But the British and American response to repeated Houthi provocation will have been carefully calibrated not to draw Iran into a direct confrontation.
The fact that the action was telegraphed from London, may have been a deliberate decision to minimise casualties and fulfil the need for a Western response without leading to a disastrous regional escalation.
Taking out the Houthi threat was vital to protect international shipping lanes in the Red Sea, which carry up to 15 percent of global cargo. The calculation in Washington and London will be that this is an unavoidable response, re-establishing the principle of deterrence and ensuring the trade arteries of world trade can flow freely.
They are aware that their air strikes carries risks of further escalation but have determined that the risk of doing nothing is far greater.