Why 1959 looked like a year of maximum Soviet danger

Why was 1959 considered a year of maximum danger from the Soviet Union?

The proposed explanation is that Soviet numerical strength became especially dangerous when its technology approached Western capabilities. The opening answer mistakenly discusses 1969 before returning to the 1959 question.

A proposed explanation for a year of maximum Soviet danger is the temporary convergence of numerical strength and technological readiness. Western equipment could initially offset larger Soviet forces, but that advantage narrowed when Soviet countermeasures reached service. The next Western technology cycle would then reopen the gap. The opening response mistakenly addresses 1969 and cites later Soviet tanks before the date is corrected. Those examples belong to the mistaken date, while the subsequent explanation applies the recurring cycle of innovation and numerical strength to the original 1959 question.