Why did Americans switch from Anti-Federalist to Federalist so quickly?

What are constitutions, and what are they good for?

When did the American Revolution end?

Were the American and French Revolutions sister revolutions?

Did the Revolutionary War lead the two sides to re-evaluate their pre-war positions?

Was the Constitution Pro-Slavery?

Why were the “wrong” states on either side of the three-fifths compromise?!