What's caused the US startup slump?

Washington

THERE'S more discouraging news about American business - specifically about entrepreneurship. We confidently assume that we have the world's most entrepreneurial nation, and the proof seems overwhelming. Google, Facebook and Twitter are but three (relatively) recent startups that have become corporate titans. Before them, there were others: Microsoft, Intel and FedEx. We seem to excel at nurturing new firms.

Or do we?