How to force subversion to restart revision number at 1 after deleting a project

No. The first import is still part of your repository. You could revert to it if you wished -this si what revision control does. If you are really on revision number 2 at this point and made a mistake on the first import, I would just delete the entire repository and recreate it.

"I'm curious as to why you'd want to do this in the first place? The revision number has no hidden meaning, it's simply an arbitrary (albeit sequential) number pointing to a specific point in time.

Of course, if you really want to anyway, I'd suggest just manually deleting the entire repository and creating it again."