Saddam was a threat to his own people. Saddam was a threat to regional peace. And Saddam was a threat to U.S. national interests, which was reason for the U.S. to take out Saddam.
Taking out Saddam was achievable. To compare that to taking out the regimes in Russia or China is absurd, as that would likely trigger WWIII.
It was known in the late 90’s that N. Korea possessed nukes. Clinton slept on the job in regards to N. Korea, Iraq, Al Quida, China (thanks to illegal campaign contributions to the Democrats) and just about every other U.S. national interest. His response to terrorism against the U.S. was pathetic, to put it mildly, which gave the terrorists license to think the U.S. could be attacked with impunity on 9/11, which occurred less than 8 months after Clinton left office, after years of terrorist planning.
Bill Clinton bears direct responsibility for 9/11 having occurred.