Last 4 sequentially:

1.) The challenge of bailing out the largest financial institutions, guaranteeing payment of $ Billions of money market accounts that either did or were soon about to break the buck, negotiating the bankruptcy of our largest auto maker, seeking buyers of near worthless securities that funded our housing market, dealing with an essentially bankrupt home funding national system, and a few other niceties...

2.) Burying 2,800 victims of an attack on our largest city, rebuilding the workplace of thousands of high paying jobs in our largest city, an attack on our capital, a decade long war dealing with said attack, solidifying at likely a $Trillion cost or more our vulnerable infrastructure and changing the business of aviation at huge expense-- forever.

3.) A global pandemic that forced the literal shutdown of our entire economy, moved everyone out of offices into their homes, brought minus 35 dollar a barrel oil, required the speedy delivery of a vaccine that still took 9 months to get to market, and pretty much killed all businesses serving city work forces which no longer existed.

3.) 1 tweet that says "we don't plan on doing anything"

I'll take number 4 thank you.