"The main concern is he will spend much of the time berating them on not spending enough on defense" before having "a love fest with Putin, like he did with Chairman Kim," Goldgeier said. He added that if Trump is warmer toward Putin than the leaders of the military alliance that was founded to protect Europe from Soviet threats, it would go "a long way to undermining NATO, undermining the trans-Atlantic relationship, undermining our relationship with our allies."