hunting (not Assault Rifles, though), target shooting or home defense...although from my perspective that's debatable since many more children are victims of accidents in the home (~1K/yr vs. ` 100 home invasions thwarted by armed homeowners)...that's real data, btw.
The fewer guns outside the home, the sager we'll all be...and this whole "Militia" thing is bogus beyond words.
Guns carried around outside the home are not needed.