State laws would be pretty much beyond the president's reach. The IRS should really go immediately, but executive orders would be limited to chomping at the bits around the edges. Congress would need to step in to complete the deed. Forcing IRS legal disputes into the regular courts (as well as requests for wire-taps) would be a good subject for such orders.

Believe me, I would go as far as I could go. The initial actions would have to demonstrate just enough that the office means business. This could encourage the other branches of government to go along.

Abolition of the State is more than one person can do, though I would do it in a blink if I could.