Sure, it may increase anti-us sentiment, but I don’t think you can confidently say that “enhanced vetting measures don’t actually provide
any protection” because there is simply no way to know or measure what didn’t happen if you didn’t have foreknowledge of the planned attack that you foiled by your vetting.
My attitude is, if you try to get in to the US you must want to be here for some reason. If that reason is to create some form of chaos, I don’t give a shit if you are made more irritated by the process. If your reason is peaceful and this discourages you…I’m sorry, it’s unfortunate, but we have folks that wish us harm and we want to protect everyone best we can…including you, Traveler.
If just being inconvenienced makes you want to harm us, well you are exactly the type of person that should probably be vetted out—and hopefully you were.