If you look at our "what to bring to camp" list, it lists "One Piece Swimsuit". This usually means more to the ladies than to the gentlemen, since swim trunks are considered "one piece". A one piece swimsuit means a bathing suit that is connected from top to the bottom. This is not mandatory, but is considered a strong recommendation.
During an average week of summer camp, our campers have several opportunities to be on the water. Swimming, water skis, tubing, kayaks, and canoes are regular scheduled events. Monday night's events also include a water component. All of these activities are highly physically active events. Many of them include Personal Flotation Devices (PFDs), but regardless, the campers are moving a lot. Your choice of wardrobe is important to how well that experience is going to go.
Ladies often have a hard time finding a swim suit they appreciate. So its natural for a camper to bring whatever swimsuit they have and would not go buy another swimsuit just for camp. The problem is not that you have girls in bikinis, but that they can not take advantage of more activities because its awkward to run, jump, throw, dive, and paddle in a two piece swimsuit. By wearing a one piece swimsuit, like a lifeguard would, a female camper can do just about anything and have little concern about what their swimsuit is going to do. Hence the word "TACTICAL"!
As far as it goes for guys, properly fitting swimsuits are important as well. You do not want to loose your swimsuit halfway down the pond while water-skiing. If you do not have an official swimsuit and plan to use shorts, make sure they will hold up to wear and tear and will stay up when they are soaked. Nylon athletic shorts usually are the worst swimsuits.
When it comes to drying out your swimsuit each day, campers have access to cloth lines around the property. Some times its easier to wrap it up in your towel and air it out at your campsite. This is a prime reason to have more than one towel. I recommend when you get back to your campsite at night, you get that swimsuit out and hang it up in your cabin. The 8 - 10 hours each night will give you plenty of time to get a dryer swimsuit.
Lastly, exposure to the sun is a big deal. You should bring sun block and make sure you use it. If you have a "swim shirt", this is a perfect "Tactical" addition.