Can the U.S. still call itself a wealthy nation?
Yes it can still be considered wealthy because it has the highest GDP. The debt is less relevant than that - the debt ratio to GDP is high but not the highest in the world. And while it potentially can cause problems, the debt isn't as bad as for some countries because the US prints its currency and therefore can't go bankrupt. Also, much of the debt is owned domestically, meaning it generates wealth for US citizens that will be put back into the local economy and therefore taxed again. So the nature of the US debt is very different from, say, a personal credit card debt. Even if it wasn't, the total net worth of the country's citizens, corporations, and governments, including debt, is vast - in the hundreds of trillions of dollars.