As a 13-year-old schoolgirl, I witnessed my hometown flattened by a hurricane-like blast, burned in 7,000-degree Fahrenheit heat and contaminated by the radiation of one atomic bomb.

Miraculously, I was rescued from the rubble of a building, a little more than a mile from ground zero. Most of my classmates in the same room were burned to death. I can still hear their faint voices, calling their mothers for help, and praying to God.

As I escaped with two other girls, we watched a procession of ghostly figures: grotesquely wounded people whose clothes were tattered or gone. Parts of their bodies were missing. Some were carrying their eyeballs in their hands. Some had their stomachs burst open, their intestines hanging out.

Of a population of 360,000 residents of Hiroshima — largely noncombatant women, children and elderly — most became victims of the atomic bombing. Many were killed immediately; some, over time. Nearly 71 years later, people are still dying from the delayed effects of the bomb, called Little Boy, considered crude by today’s standards for mass destruction.

This same city, rebuilt over the decades with few reminders of its tragic past, will soon play host to President Obama, as he becomes the first sitting U.S. President to journey to the place where nuclear weapons were first used in war. For me, and for many survivors, this historic occasion presents a conflict of emotions. Of course we appreciate the courage it takes to come to Hiroshima, especially given the current political climate in the United States.

But still we are frustrated by Obama’s eloquent propensity to say one thing and do another.

In his famous speech in Prague, in 2009, he said, “As the only nuclear power to have used a nuclear weapon, the United States has a moral responsibility to act. We cannot succeed in this endeavor alone, but we can lead it, we can start it.”

Why then has the U.S. government, under the Obama administration, pledged $1 trillion over the next 30 years to modernize its nuclear arsenal? Exactly where is the moral responsibility and leadership in that?

Regarding disarmament, Obama stated, “Our efforts to contain these dangers are centered on a global nonproliferation regime, but as more people and nations break the rules, we could reach the point where the center cannot hold.” Why then are the U.S. and other nuclear weapon states actively boycotting the latest international nuclear negotiations?

If the President is serious about disarmament, he should have sent a delegation to the UN in Geneva, where, this month, representatives from nearly 100 countries discussed the prospects for a nuclear ban treaty.

Currently endorsed by 127 nations, the nuclear ban treaty is the most significant advance for nuclear disarmament in a generation. Yet there is little attention in the media, so the public remains unaware.

The President also made the bold and accurate claim that, “If we believe that the spread of nuclear weapons is inevitable, then in some way we are admitting to ourselves that the use of nuclear weapons is inevitable.”

It is crucial to understand that this use may result by design or by accident. Indeed, nuclear risk is on the rise as accidents and aging infrastructure have been revealed in recent research, proving that the very existence of nuclear weapons presents an avoidable threat to life on Earth.

Let us not forget that within two flashes of light three days apart, two beloved cities, Hiroshima and Nagasaki, became places of desolation, with heaps of rubble, horrifically wounded people and blackened corpses everywhere.

He may be courageous to visit Hiroshima, but the President’s symbolic and rhetorical courage must be backed up by action for disarmament.

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— Article by Setsuko Thurlow; a former social worker and founder of Japanese Family Services of Metropolitan Toronto, is an advocate for nuclear disarmament.