It's kind a funny when you think how the smartest race on this planet can be wiped out in a a relative small time frame because of a few idiots or a simple malfunction.
Well..... the command structure right now is different from what we had in the 1960s. Russian and American nuclear weapons can be launched only by the respective heads of state. And that too after receiving permission from other top level staff such as the Secretary of Defense and the Chairman of the Joint Chiefs of Staff. And regarding malfunction, it will never happen. These weapons will become dormant / inactive if any malfunction occurs.