Earlier quoted context omitted.
It still is. Most nations' Commanders in Chief (i.e. the Presidents) have the power to order a nuke launch by themselves. Of course they have advisers and so on, but that does not mean they have less of a power.
Under US protocols, only the President can authorize the use of nuclear weapons, however the Secretary of Defense must also approve the use.
I wasn't only talking about the US. There are many other countries in the world who own nukes and where their usage protocol is different.