You don't actually need JavaScript for modals, but it would hinge on how many items you have on a page that can be deleted.
Traditionally I like to write it so that it works without JavaScript via page-loads first for accessibility and to hammer out / test the logic, then ENHANCE the page with JavaScript that calls the exact same database handling routines but with a cleaner client side rendered interface using JSON or XML to avoid the page-loads if the client really desires it.
But remember, pageloads are NOT inherently evil or bad, and should NOT be any different than the scripted approaches apart from leaving a page you might not want to leave.
Rule #1, quality JavaScript should enhance an already working page, not supplant what can be done without it. If you can't make a fully working page without scripting first, it's very likely you have no business adding scripting to it.