"Despite my deep disappointment regarding our nation's choice to engage in a pre-emptive war for no good reason."

Iraq wasn't a pre-emptive war. Iraq invaded Kuwait, was forced out Kuwait by Coalition countries [mainly lead by the US], Iraq signed a cease fire agreement, and thereafter violated this agreement. The US had the legal authority from UN Security Council to use whatever force was considered neccessary to resolve the conflict which Iraq began. And someday in the future we can look forward to the time that Iraq as a country will finally resolve the war that Saddam started by invading Kuwait. And even without considering the UN, the US had the legal authority to enforce the cease fire agreement.
Neither Iraq or Afghanistan were pre-emptive wars. Pre-emptive war has been discussed. And many think we need to modify international law to deal with threats which are associated with the spread of WMD, especially in regards to situations in which deterences wouldn't be effective.