Parsing out the exact impact of the European crisis on the US economy can be difficult. There's a strong chance that Europe can wound the US, and the cumulative effect could be drastic. The danger doesn't come from where you would expect -- exports from the US to Europe. Though turmoil in the region certainly poses a risk to US exporters, for the first quarter US exports to Europe were up more than 8%, to $86 billion. RBC Capital Markets chief US economist Tom Porcelli believes Europe's troubles may hit US exports in a more roundabout way. If Europe continues to deteriorate and its financial system tightens, some emerging markets could lose a key source of financing, which in turn could squeeze their ability to keep buying US goods. Another potential point of contagion is the US financial system's exposure to Europe's souring debt, particularly that of Spain and Greece.