When I hear the word (tactical), I think of battle tactics; warfare; maneuvers involving the use of weapons. Nowadays, it's nothing but a markering term used by manufacturers to make their products appear more attractive. We see this term "tactical" used with with knives, boots, watches and other gear.
Basically, it works like this: One manufacturer specifically designs or markets flashlights towards the military and/or law enforcement. Certain features are highlighted, such as type III hard anodizing, tailcap switches, CNC machining, the ability to manipulate the flashlight in conjunction with a firearm, etc. Naturally, these features will add to the cost of these lights and will tend to price them beyond the reach of the average consumer.
Eventually, these lights make their way to the civilian sector and now there comes a demand for flashlights with these so called "tactical" features for the average Joe. Other manufactures see an opportunity to boost sales and borrow upon those features in order to stay competative in the market and begin to produce these so called "tactical" lights at more "affordable" prices. Obviously, many of their products are tailor-made for military or law enforcement personnel, but they will appeal even more to what I like to call the "keyboard commando" types.
The confusion arises when the market gets flooded with so-called "tactical" lights whereby almost every flashlight with a tailcap switch is marketed as "tactical" even though realistically it is designed for light duty commercial use.
Now, ask yourself this question. What is a tactical flashlight? Is it one used by the military or by police? If that's the case then all those plastic government issue Fulton MX/991 anglehead flashlights (which are still seeing action in Iraq and Afghanistan) are tactical lights as are all those D cell Maglites some cops still carry.