The answer appears to be the developing world, or emerging markets. Granted, whenever someone talks about “emerging markets” they usually wind up focusing on China – which definitely carries a lot of risk in terms of both currency value (fixed by the still communist government) and slowing growth. But throughout the rest of the planet there is opportunity. Lots of it, in fact.
While the US still looks great as a “safe haven” there is plenty of reason for cash to start flowing back to the developing world. But that investment is almost certainly going to be led by US investors given the strength of the US dollar.