Just over 50 years ago, the earth as we know it came dangerously close to being engulfed in a nuclear fireball.
In October 1962, the United States commanded the Soviet Union to dismantle and remove nuclear missile sites in Cuba. After the Soviet Union refused, the U.S. established a Cuban naval blockade.
With the situation quickly escalating toward nuclear war, Pope John XXIII issued an urgent appeal for peace.
In a letter to President John F. Kennedy and Soviet Premier Nikita Khrushchev, Blessed Pope John XXIII pleaded, "We beg all governments not to remain deaf to this cry of humanity. That they do all that is in their power to save peace. They will thus spare the world from the horrors of a war whose terrifying consequences no one can predict."
A few days later, Khrushchev agreed to withdraw the missiles.
The Cuban missile crisis had ended, but it had a profound effect upon Pope John.
Just months later in April of 1963, he issued his prophetic landmark encyclical letter Pacem in Terris  ("Peace on Earth").
Mindful of humanity's recent close brush with nuclear war and the devastation conventional war causes, he wrote: "Justice, then, right reason and consideration for human dignity and life urgently demand that the arms race should cease, that the stockpiles which exist in various countries should be reduced equally and simultaneously by the parties concerned, that nuclear weapons should be banned, and finally that all come to an agreement on a fitting program of disarmament, employing mutual and effective controls."
Tragically, Blessed Pope John's appeal to justice, right reason, and consideration for human dignity and life is largely ignored when it comes to ending the arms race, banning nuclear weapons and moving toward verifiable multilateral disarmament of all weapons.
Big money is a gigantic obstacle here. War making and war preparation is an extremely lucrative business.
According to the Stockholm International Peace Research Institute , worldwide annual military spending is approximately $1.7 trillion. The U.S. spends about 41 percent of that amount.
In Pacem in Terris, Blessed Pope John astutely observed if one country is equipped with nuclear weapons, certain other countries feel they must produce their own "equally destructive" weapons.
Nations possessing nuclear weapons need to set a good and credible example by moving toward the elimination of their stockpiles as specified by the Treaty on the Non-Proliferation of Nuclear Weapons. GlobalZero.org has a list  of ways you can help.
Without this good-faith effort on the part of the nuclear powers, more non-nuclear countries will seek, as Pope John observed, their own "equally destructive" nuclear weapons.
North Korea is a clear example of this dangerous cycle.
As I write, North Korea's military posturing could lead to war -- nuclear war. But tough talk and muscle-flexing from South Korea and its U.S. ally only fuels the tension.
Instead, as Pope John wrote, "Disagreements must be settled, not by force ... but rather in the only manner which is worthy of the dignity of man, that is, by a mutual assessment of the reasons on both sides of the dispute, by a mature and objective investigation of the situation, and by an equitable reconciliation of differences of opinion."
And as good Pope John wisely counseled, solid and true peace will be born when human rights are universally respected, and when equality of arms is replaced with "mutual trust alone."
Editor's note: The translation of Pacem in Terris used in this column is found in Renewing the Earth: Catholic Documents on Peace, Justice and Liberation. EWTN provides the translation .
[Tony Magliano is an internationally syndicated social justice and peace columnist. He is available to speak at diocesan or parish gatherings about the principles of Catholic social teaching. His email address is firstname.lastname@example.org .]
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