How Much Oil Do We Really Have in America?

I did a little research when all of that "drill baby drill" noise was going on to find out just how much oil we have on land and off shore in America. I found that all in all we have about 21.2 billion barrels total.
We use 7.14 billion barrels of oil per year.
That would mean that if all those platforms out there could suck out every drop of oil under our surface, it would give us enough oil to last about 3 years. Is it really worth it? It doesn't go to us. It's not like they drill on our land and we get cheap gas for it. It goes onto the world market and is speculated on until it's the same price (or more, as you may know the price of oil is building a bubble again) that the rest of the world pays for it. We drill for the profits of the oil industry, not to give us lower prices at the pump. It's time to move to renewables. We are becoming the last at everything. I want to see us become the leaders in future-tech in the world. I'm embarrassed by the backwardness we show of ourselves by refusing to move from carbon to clean. The oil companies manipulate the masses into believing everything is just fine. Yeah, fine for them as they rake in record profits.
Let's get a move on. Let's take the lead. Be the leader again in SOMETHING besides weapons manufacturing.
Shelley