If you take a small selection of basic tools with you, you will never need them. The one time that you don’t have a Phillips screwdriver is the time your life may depend on it.
A partial list:
Screwdrivers–Phillips & regular
Smallish hammer (like tack hammer)
Pliers, both regular & needlenose, also big vise-grip (locking) pliers
DUCT TAPE (somebody already said that, but I can’t emphasize it enough)
Big roll of baggie tie stuff–garden centers usually have this, to tie up climbing rosebushes (or lots of baggie ties)
Pair of big scissors that you don’t care what happens to
Big sawtooth edge knife, ditto (like a big bread knife)
If you have some around, bring a roll of electrical wire, like you use to rewire a lamp (not extension cord stuff). What with the duct tape, baggie ties, and wire, you can fix anything loose.
Coil of nylon rope or clothesline–use it for wet clothes, to tie the bumper back onto the truck, 101 other uses…
Clothespins, if you can find them
Pair of flipflops for wearing down to the “comfort station”
One of those 4-battery cop flashlights, for nighttime trips down to the “comfort station”–and don’t skimp on the batteries, get the good kind, and lots of 'em
Big Hefty sacks, for trash and also emergency poncho (don’t laugh, it works)
Campfire stuff:
Matches
Stack of old newspapers
Buy your firewood at home before you go–sometimes the prices they charge at campgrounds are extortionate.
Something to sit on, next to the campfire.
WIENER FORKS. Geez, I can’t believe I almost forgot the wiener forks. Oh, noooo–and MARSHMALLOWS!! << smacks self in forehead >> also fixins for s’mores, if you should be so inclined.
Also: bug repellent, or else you may as well go home.