While I think the economy faces, both short-term and long-term, some serious problems, James Pethokoukis makes some good points in "Why the Economy Is Better Than You Think".
If you could swap the American economy for someone else's long term—China's, India's, the EU's—would you? . . . China, for instance, has far worse demographic problems, has far worse environmental problems, will probably never catch America in terms of per capita GDP, and, by the way, still needs to fully transition to democratic capitalism. America? It's in far better shape that you think.
On the other hand, there's this: "The Train Wreck Ahead: Medicare is rolling toward disaster, and there is no easy way to fix it".