With a 20 year head start she might be able to actually do it, maybe by becoming president or head of the cdc or something?The ability for a time traveler to prevent 9/11 with one day's notice is... definitely going to be more difficult.
Fun fact, we did have a 20 year start on COVID. This was bird flu, SARS, MERS, swine flu... Scientists have been saying this was coming foreverThis was basically as prepared as we could get. There were protocols in place for everything
Call a bomb scare into WTC and park a suspicious van outside of itCall ATC and the FBI and tell them the exact flight number(s)You can save lives, though not all
Ah yes, COVID, the most immediate threat to global commerce and geopolitical stability on September 10, 2001💀
Unexpected Twelve Monkeys