Steering wheel wiggles when driving

This is for a 98 Plymouth Voyager...
So while driving, the steering wheel wiggles (or shakes) constantly left and right.. but it only wiggles within a 1cm or maybe less than half an inch range. When I let my hands off the steering wheel, it tends to be crooked towards the right... so the van pulls to the right and never goes straight unless I hold the wheel in place. And even then, I can kinda feel it trying to pull to the right. I know the psi in the tires are even. Could this be an alignment problem? or something's loose?

get it alligned and then balance the tires.

check the tie rod ends.

Gen3 Chrysler minivans are very sensitive to belt problems in tires. If you have the original Michelins that would certainly be the reason. Chrysler has a Technical Service Bulletin related to this!! It is very likely you have a bad tire on the front end. Try rotating them and see if it changes. If it does then new tires are the fix.
Also, if the steering wheel is offcenter, it is likely you will need a front end alignment regardless!!