I heard they gave a 2 hour advanced notice of their attack, but that could just be fake news.
Given that Trump said there would be consequences if U.S. lives were lost and there were with the death of the general and others, probably not the wisest idea to push any more boundaries or try and call a bluff.
This seems a fairly logical set of events when you look back. Red lines drawn in the sand, hollow and meaningless threats, appeasements etc. A lot of long term good could come from all of this, we can hope anyway.
Threats, obviously are meaningless, toothless unless you follow through. Once it's clear you will follow through and people know where you stand and that you will do what you say, it does make things easier in many ways. Consistency and predictability has it's advantages far more than drawing red lines in the sand.