By that logic 2000 is the last year of the second millennium, 2001 is the first year of the third millennium, 2002 the second, and 2003 the third.

The era started at year 1, and not year 0. So the new millenniums starts at years that ends with 1.

It’s also the third millennium of the era. 1-1000 AD was the first, 1001-2000 AD was the second, and we are now in the third.

If he doesn’t end up as VP, he would be a good candidate for Mitch McConnell’s senate seat when he retires in 2026.

Sure, and a window on the fifth floor is technically an exit. But that doesn’t make it a viable option.