I don't deny that US is still by the far the greatest country on earth currently. In fact I said that myself.
But there is no such thing called as a permanent super power, nor there ever will be.
Everything that you wrote about US, could have been written about any super power in History. The Romans, The Mongols, The Greeks they all were super powers with similar traits. And yet none of them are a super power today.
You underestimate how decadence works. There are a lot of Chinese and Indians who no longer want to come to US. And it takes a very few companies to change the economic momentum of the world. If past is any indication, you could even alter the very direction of the human race with a few inventions/enterprises, and you can do it quickly.