There are more than 14,000 nuclear weapons in the world. The United States has a little more than 6000. Actually Russia has more.
Games theorists and arms negotiators would say that unilateral disarmament is taken as a sign of weakness that invites attack. With such an adverse world social environment the United States would be remiss in looking after self-defense to unilaterally disarm.
The Tsar bomb of the Soviet Union- the world’s largest that was exploded at Novaya Zemlya, it is said, if exploded at the right depth of the Marianas trench would destroy the world causing gross tsunami and tectonic plate disturbances, earthquakes etc. Plainly nuclear weapons are a threat to humanity.
It wasn’t the United States that began the first or second world wars. The U.S.A. and it’s allies finished it. The nuclear big three are those nations that fought against the axis powers. Humanity has generally not shown a level of maturity that would foster such trust that any super-power would disarm as Pres. Ronald Reagan sought to do. Surprisingly for some, President Reagan’s goal was complete nuclear disarmament. Unfortunately in the aftermath of the Cold War, and after the substantial reductions in nuclear arms, President Clinton levered Boris Yeltsin to give up the Ukraine and Crimea that had historically been integral parts of Russia, and that caused lasting enmity. The west has been hostile to Russia for some time, and Europe is hardly a trustworthy partner for Russians that have suffered European invasions repeatedly in history with the loss of tens of millions to wars.
There are other weapons of mass destruction besides nuclear that are challenges to world survival today that need also be addressed. Persistent solid nerve agents such as Novichok recently used in England are grave threats to population centers. Biological weapons are radically dangerous with all the genetic recombination technology, and the list goes on.
Because economic reform as well as an update of the theory of capitalism have not been synced with ecospheric renewal the implicit instability of geopolitics render complete disarmament improbable. Without faith in Jesus Christ the problem of original sin prevails.