Even though there is no direct damage that can be caused to the U.S. by Greece; however, it is the overall tension in the EU that might be detrimental to the States.
Firstly, it is important to highlight that the banking system in the U.S. might be in jeopardy due to sovereign debt. Even though the debt for Greece USD 5.8 billion is minor in comparison to the overall banking organism, the exposure is greater to other larger economies such as Italy and Spain with USD 66 billion and USD 50 billion respectively. On top of that, the key threat lies in the scenario if the financial markets halt due to Greece's default of the euro.
Secondly, the Euro area is in fact the 3rd biggest U.S. export region after Canada and Mexico, which accumulates to 13 per cent or USD 49.2 billion of the total exports. Therefore, if Greece withdraws from the Euro area with together other smaller economies this would negatively impact the U.S. exports.
Finally, another risk worthwhile mentioning is that a number of large U.S. countries produce their goods in Europe for the European target audience. Hence, if the EUR vs. USD progresses to fall, the U.S. companies may face the risk that their goods made in Europe become cheaper than those in the domestic market and consequently deteriorate sales in the U.S.