This is a scenario which could go either way. Let me give an example in a different way.
Some people can protect their property against bears by putting an electric fence around their homes. However, this will only work if the bear "knows" by experience what the fence will do to him if he touches it. My guess is that it will be the same for any type of flashlight, tactical or otherwise.
But will a tactical flashlight really work against black bears? Well now: Let's ask a bear!
When police cars turn on their flashing lights, it gives you a little bit of a start, no? Me too: According to the Colorado Division of Wildlife, flashing lights can startle me and cause me to flee the scene.
But there's a problem: It will most likely only work once. Unless something happens to reinforce the light (i.e. you yelling, banging pots, etc.), I'll learn to call your bluff. You might get a few more scares out of me by altering the pattern of lights, but eventually I'll figure out that there's nothing to them. If you're camping in a location with highly motivated problem bears used to raiding camps, it might not even work at all.
In either case, the best option for you is to keep all smelly items (food, toothpaste, deodorant, you know the drill) in a canister or in a properly hung bear bag far from camp. Since you're in the dark, it's probably best for you to use a locking canister, since some of us up there know how to open screw-top canisters.
Flashing lights are sometimes recommended for houses with bear problems, but lighting systems can be heavy or problematic to camp with. And how will you sleep with all those flashing lights?! Even with blinders on, you could be ruining the wilderness experience you came for in the first place. Never mind the bears — I think you'd have more trouble from fellow human campers who come from far and wide to see what that annoying flashing is all about. - Ask A Bear: Scared By Flashing Lights?