One has to admire the dedication, courage, and strength-of-will that is inherent in any officer who decides that ship's security is a life pursuit. Must protect the Captain at all costs. Must be willing to risk life and limb for the safety of the ship and her crew. Must hold the front line. And always, ALWAYS be ready to take one for the team when the Captain orders you to accompany him to the surface.

The shirt color is designed to lessen the visual bloody impact when lethal, non-energy weapons are involved.

But I've never understood why the security guards of the fleet's flagship would be so inadequately-equipped. Red shirts are usually the slightly tougher-looking brutes compared with the rest of the crew, but aside from their scrutinizing smug, all they have are hand phasers and shirts that read "shoot me." What, no "tactical" gear? On an alien planet?

In space where there's a new alien threat on a weekly basis, you'd think body armor would be a obvious. How about a back-up phaser type I at least?

At least in the TOS movies they showed some body gear:

What about tactical training? Did Starfleet lose their agility (and common sense) in this area? In this example, you'd think these two would take cover behind a corridor corner before pointing a weapon at Nomad:

or not stand out during combat in the battlefield:

Being in security involves weapons of all types. Must have the right tools for the job ... but whatever happened to the corny-looking phaser type III rifle-thing the brave Captain was lugging around when hunting for Mr. Mitchell? Surely the security forces would occasionally be seen with these at some point in the three seasons of TOS.

Maybe they just didn't want to be made fun of by the aliens when they pulled out what looks like a classic "ray gun" that will squirt electric phaser zaps. There's just nothing cool about carrying around a sidearm that can be spotted in the dark from orbit.

Now I understand that the Enterprise is a ship of peace and therefore the crew should be representative of this philosophy. Uniforms should also convey this attitude ... but this just makes the security team members easy pickings. It's the same deal in the new alternate time. Check out "Cupcake" here:

We rarely get to see any of the red shirts perform half-decent hand-to-hand combat (at least by Kirk-fu standards). However, we do get to see Red Shirt Montgomery in action when Commodore Decker takes matters into his own hands in "The Doomsday Machine":

You would imagine that a Starfleet security force is much like today's military personnel in sharp uniform, following a strict code of conduct, marching in sync, and able to hold a nice clean honor guard line during ceremonial affairs. Not so on the Enterprise as demonstrated in "Journey to Babel":

Over in the 24th century, things haven't improved much. During the initial boarding by the Borg, Picard orders Worf to stop the intruder. Worf orders Ensign Expendable to handle the Borg. You know what happens next.

At least you get to see the occasional female security officer on Picard's Enterprise. This probably wouldn't happen on Kirk's ship.

She does, of course, take one for the team a few moments later.

Speaking of Captains, some of them even think picking off their own is justified as evidenced when Captain Tracey in "Omega Glory" did one of Kirk's in:

So when you sign-up for Starfleet Academy, beware the shirt color you're going to receive because with the wrong one your chances at promotion are slim to non-existent. Being expendable, under-armed, under-trained, and uncared for by your superiors in a state-of-the-art space fleet a few centuries from now with supposedly immensely powerful technology is a thankless job, but somebody's got to do it.