Hegseth put all the information into the Signal channel two hours before the expected strike would take place. It was less than two hours before the operation began - the first wave of F-18's were to take off a half-hour later - but two hours before the first window for the targets were to be hit. Per the message, the first strike window for the first wave of attack began at 13:45 - two hours after his 11:44 post.
If the Houthis had two hours advance notice that the U.S. was going to try to strike a high-value individual and with what weaponry, that news would have been unbelievably valuable to thwart the attack. If they had access to that information, at a minimum they would have simply moved their high-value folks away from places they would be known to frequent - and they would be able to figure out which locations would be good hiding places, knowing that the U.S. was attacking with those weapon platforms (as opposed to others). And they'd know the exact time it was going to happen.
Which is why the Republican head of the Armed Services Committee isn't pretending that this was innocuous information. This would have been and should have been classified and protected information.
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