There has been a pro-Russian thread to German foreign policy ever since it became a single unified nation in 1871. Bismarck had the Reinsurance Treaty; the Weimar Republic made a secret deal with the Bolsheviks to facilitate rearmament; Hitler agreed to the Molotov-Ribbentrop Pact in 1939; and some German politicians promoted Ostpolitik during the Cold War days.
Trump and his advisers plan to slap tariffs on German exports and to bully the Germans into spending far more on defense than they do today. What if Putin offers them cheap gas and a non-aggression pact in exchange for acquiescence to Russian dominance in Ukraine and a refusal to rearm? It would save the Germans a lot of money at a time when their economy is struggling.
Trump probably believes this option is unthinkable, so the Germans will ultimately have to kiss his ring. History and common sense tell us he’s wrong about that.