What seems to be his opinion is the danger of giving so much power in the hands of only one man (in this case the John Kennedy as the President of the USA and Nikita Khrushchev as First Secretary of the Communist Party of the Soviet Union). Never before the nuclear weapons one human being has had such a destructive power. In his other podcasts, he alerts about this danger in the current political environment as Obama worked to concentrate even more power in the presidency during his time and we never know who might end up being president in the future, it is a very risky thing to do. For some, Trump is the personification of this exact risk; but for others, who support Trump now, it worth thinking that they don't know either who might end up next at the presidency with all this power.