What Germany?
I've had enough candidate conversations with German to hear the talk about dominating Europe, impatience with other Europeans countries holding Germany back, etc.
Most Germans will publicly disavow militarism and a desire to change European boundaries, but enough little jokes about conquering Europe economically, and knowing how hard Germans work compared to other nationalities in Europe, how much of the burden of the EU Germany is shouldering, etc.
I do not think that a revival of the NSDAP is around the corner. Most Germans acknowledge Germany was defeated in 1945, deserved to be defeated in 1945, but since 1989, Germany has recovered (most of) her lost territories (less Pomerania, Silesia and East Prussia). But in a Europe in which America is not playing a role (the question at hand), and one in which the second largest economy in Europe (the UK) may well secede and resume her splendid isolation (the "Brexit"), is a Europe in which the Franco-German rivalry might resume and I believe Germany would dominate that rivalry fairly handily. (GDP comparison France: $2.3 trillion, Germany $3.2 trillion, and the gap has been growing over the last few years. The US, by comparison, is $15.68 trillion.) How long would that economic imbalance have to grow before the Germans would try to turn that economic might into some political muscle? I don't know.
A Europe in which the US is involved is better for the US, better for Europe.