Apparently he's threatening to pull out of NATO if EU countries don't spend 2% on their own defence.
He's right on the demand but the threat is fairly extreme.
On the other hand, the complacency of countries like Germany is set in thick cement.
They, in particular, have been freeloading. The gas pipeline agreements between Russia and Germany, with former chancellor Schroeder a beneficiary, looks as dodgy as a Trump university.