The US pulling out of the Paris Agreement was a mistake, not because Man is the leading cause of global warming (of which I am still not convinced), but because it moved the US further into political irrelevancy on a global scale.
Look at China, the filthiest and grossest of polluters of all industrial nations (a living mockery of the Paris Agreement). Yet China remains with the Paris agreement. Why? Not because they care about the environment (they most certainly do not), but because they are playing the long game. They are patient, while Americans are impatient and pragmatic.
Now Germany will begin to distance itself from the US and likely bolster ties with BRIC nations like India and China. Why? For one, Germany may be the only nation on the planet that actually cares about the environment for non-political reasons. The environment is a nationalistic passion of theirs, second only to their love of soccer. Second, the Germans smell death on the US Empire. They sense the change in winds, and its more than the grotesque flatulence of a certain US leader.
The US staying in the Paris Agreement would have been expensive economically in the near term. The US will find that backing out will have its own costs, which will have long term economic impacts of their own.