The full faith, credit and taxing power of this state are irrevocably pledged to the payment of the principal, interest and premium due, if any, on all public debt. There is irrevocably appropriated through s. 20.866, as a first charge upon all revenues of this state, a sum sufficient for the payment of the installments of principal, interest and premium due, if any, on all public debt as the same falls due.
Wis. Stat. § 18.12