Why is it that here in the US most motorsports circuits go counterclockwise and not clockwise?

May be...

The oval tracks go counter clockwise because the first races were held at horse racing tracks and the horses always ran counterclockwise.

There are road racing circuits that run clockwise like Infinion in California.

Running stock cars on a clockwise oval would be dangerous for the drivers because the driver sits on the left side of the car and would be more vulnerable to a crash into the wall.

what would it be like if a US racetrack would go clockwise, would there be anything bad that would happen, or anything, really?

Since the northern hemisphere is closer to the north pole and water goes down the drain in a counterclockwise revolution, except for the earth inertia, their would be no catastrophic effects of driving clockwise, except for shorter tire life,engine life, and wear and tear and lower speeds, since the laws of physics bend for no onesearch seizure student