Gore’s presidency would have been a continuation of Clinton’s, who were aware of the threat potential posed by al-Qaeda. So if/when the now infamous Bin Ladin Determined To Strike in US memo landed on his desk on August 6th, 2001 - or the even earlier “UBL [Usama Bin Laden] Threats Are Real" memos from months earlier; they would have been taken seriously and acted upon.
Instead Bush's response was to fob it off disinterestedly, saying: "All right. You've covered your ass"
So yes, learning from earlier failings - a theoretical Gore presidency would have taken these threats much more seriously, and could have prevented the thousands of deaths of 9/11, and tens of thousands of deaths in the subsequent wars.