In this 1998 letter Rumsfeld, Perle, Wolfowitz and others call for regime change in Iraq and urge Clinton to undertake miltiary action

The only acceptable strategy is one that eliminates the possibility that Iraq will be able to use or threaten to use weapons of mass destruction. In the near term, this means a willingness to undertake military action as diplomacy is clearly failing. In the long term, it means removing Saddam Hussein and his regime from power.

even without UN Security Council support:

In any case, American policy cannot continue to be crippled by a misguided insistence on unanimity in the UN Security Council.

Bush’s boss has been after this for years.