Every reasonable person should hope there will never again be any use of nuclear weapons in war.
At the same time, every American should rejoice that U.S. nuclear weapons dropped on Hiroshima and Nagasaki in Japan in August 1945 ended World War II quickly with U.S. victory.
Those American nukes surely saved the lives of thousands of American soldiers by eliminating the need for U.S. invasion of Japan. And thus our nukes surely saved the lives of countless Japanese, as well.
Although nukes have never been used in war since those fateful days when the United States was the only possessor of nuclear weapons, many other nations have since developed nuclear weapons of their own. That has created a nagging threat.
The United States has been forced to modernize and retain a huge nuclear arsenal with the desire that that will be sufficient to prevent any other nuclear weapons possessor from initiating nuclear war.
Perhaps the greatest nuclear weapons danger today is that nukes might fall into the hands of some irrational group that might not be deterred from using them.
While we hope there will never be nuclear war again under any circumstances, we live in an unstable and irrational world. So there is no reason, certainly no "need," for the United States to give any "assurance" that our nation would not use nuclear weapons under any circumstances.
Non-threatening friends need no such pledge. Potentially threatening enemies do not deserve any safety guarantee.
So it was unwise, and certainly unnecessary, for President Barack Obama to bring up the nuclear arms subject in a way that suggested the United States would not use nuclear weapons -- even if needed in self-defense -- with only two exceptions.
What exceptions? President Obama mentioned "outliers like Iran and North Korea."
Communist North Korea is known to possess nukes. Iran reportedly has been trying to develop nukes. The regimes of both of those countries are so irrational that there is no reason to feel sure they might not use them under some circumstances.
But why should the United States handcuff itself so far as nuclear weapons are concerned?
The United States threatens aggression against no one, with any kind of weapons. But we cannot predict with certainty what threats to us may arise. We need to retain superior nuclear arms power to heighten the probability that our capacity will be sufficient to prevent even some foolish nuke possessor from challenging us with nukes.
The best guarantee that no one will ever suffer nuclear war again is American nuclear superiority that can assure any threatening nation or group quick defeat and death.