When I came back in France during Christmas, the whole downtown access to a city was restricted, with checkpoints at every bridges. It slowed normal people for control multiple times a day. But because this "security" wasn't present 24/7 any islamist could import weapons at night and make a carnage during the day, with the additional effect of the checkpoint slowing people from escaping the area under attack. Hopefully, there wasn't the budget to employ national police for all the checkpoints, so technically you could cross them without any security people having the right to stop you, which I did one time.
https://www.huffingtonpost.com/2015/06/01/tsa-fails-95-perce...
There is a term for what you described, security theater. I'm not saying it's worthless, but it's only not worthless because terrorists might believe it's not.