Without him, it's very unlikely that US troops would be stuck in Iraq, fighting his illegal war. They'd be in Venezueula, etc. Latin America wouldn't be taking an independent path from the USA for the first time in decades. (BBC story). In a year or so, Mexico will be the next country to turn leftwards, since the whole NAFTA thing has been a disaster for them as well as us...

He might have had enough political clout to push through his Social Security privatization. Clinton repealed welfare and was about to privatize Social Security; Monika saved us from that idea...