Do mechanical engineers invent weapons

I'm not near college, but I am fairly aware of these things... There is a career titled "Weapons Engineer", as there are different types of weapons and such, you would need different backgrounds in engineering.

Mechanical Engineering: This leans more towards hand-held weapons (handguns, assault rifles, etc.) but it can also mean mounted weapons (.50 calibers)

Electrical Engineering: This will lean more towards radar, radar jamming, smart weapons, etc.

Now the bigger your looking for (missiles, rockets) the more you will want to think about Aerospace Engineering...

I hope that, that had answered your question... but like I had said I'm not near college... I am in the 8th grade, but I want to do something of engineering or architecture so I am well read up on this.