communism. >> madman theory is to basically use unpredictable, seemingly brash, bravado, over-escalation to get the other side to fall off its positions. >> reporter: trump has used similar questions about how he would handle foreign computations. refusing to rule out nuclear weapons. >> i can't take anything off the table. >> reporter: calling for ban on muslims. >> total and complete shut down of muslims entering the united states until our country's representatives can figure out what the hell is going on. >> and most recently taking a call from the president of taiwan. a break from with diplomatic tradition billed as a calculated ploy for leverage. >> i don't know why we have to be bound by one policy unless we make a deal with china doing