I don't know if your question is serious or supposed to be some kind of joke. Either way the definite answer to your question is no for a number of reasons. Germany is one of the biggest members of the global political economy. A lot of their companies have business interests with the rest of the world, look out your window and count how many BMWs, VWs, Audis, and Benzes you see. Also pop the hood of your car and see if there are any Bosch parts. Second, Germany is also a NATO ally, meaning they would either have to withdraw from NATO or violate the treaty and attack a NATO member which would be suicide. However I don't think there are any countries that dumb. Third, I wouldn't be too concerned about Germany attacking us rather who we will attack next.