Germans migrated to america because of the following three reasons:
continual warfare among the many german states
religious persecution of the protestant peasants
heavy taxation and seizure of property by the warring factions
being faced with economic ruin
being forbidden to ship their dairy products, linens, and woolens to english markets

As far as I remember, during this period Germany was feudal fragmented, and there were no economical opportunities to stay there until it will be unificated. And I see at least three reasons for germans to migrate to America:

Continual warfare among the many German states
Religious persecution of the Protestant peasants
Heavy taxation and seizure of property by the warring factions