Thlayli
Le Pétit Prince
I agree, silver/NK. The Germanics weren't that adept at waging war in the 1st century, or organized, and if Rome made a significant push all at once, the local tribes could be crushed or made subservient in the same manner as Gaul. IMHO, taking and "pacifying" Germany wouldn't tax Roman resources of the Early (not Late) Empire any more than crushing Judea would.