Pompeo was speaking to reporters on Wednesday about U.S. nuclear disarmament efforts as this month marks 75 years since the country's atomic bombings of the Japanese cities of Hiroshima and Nagasaki.
The atomic bombing of Hiroshima on August 6 and Nagasaki three days later killed hundreds of thousands and accelerated Japan's surrender in World War II.
Thursday's event was hosted by Peace Quest Cape Breton whose co-ordinator, Sean Howard, a CBU adjunct political science professor, told his audience that the struggle to rid the world of nuclear weapons is far from over.
People offer a silent prayer at 8:15 A.M., the exact time an atomic bomb was dropped on Hiroshima 75 years ago, during a ceremony to mark the anniversary at the Hiroshima Peace Memorial Park on Thursday.
But the general public was kept away, with the ceremony instead broadcast online. "It's frustrating, but there is not much we individuals can do".
"Hiroshima considers it our duty to build in civil society a consensus that the people of the world must unite to achieve nuclear weapons abolition and lasting world peace", he said.
Japanese Prime Minister Shinzo Abe (C) bows in front of the Memorial Cenotaph after delivering a speech during the 75th anniversary memorial service for atomic bomb victims at the Peace Memorial Park in Hiroshima on 6 August 2020.
Japan, which sits under the US nuclear umbrella, has refrained from becoming a signatory to the Treaty on the Prohibition of Nuclear Weapons - the first legally binding global agreement to comprehensively prohibit nuclear weapons.
"I ask the Japanese government to heed the appeal of the [bombing survivors] to sign, ratify and become a party to the Treaty on the Prohibition of Nuclear Weapons, " Matsui said".
International Campaign to Abolish Nuclear Weapons (ICAN) wrote, "We remember the victims of the dawn of nuclear weapons age in Hiroshima and Nagasaki, and we honour the survivors who seek the sunset of that age by joining in their fight to ban nuclear weapons.".
Some survivors and their relatives visited and prayed at the park's cenotaph hours before the ceremony began.
"Japan's position is to serve as a bridge between different sides and patiently promote their dialogue and actions to achieve a world without nuclear weapons", Abe said. Guterres' expected visit to Hiroshima had to be cancelled because of the coronavirus.
Unlike past observances, only the "hibakusha", as the survivors are known, their families and a few dignitaries were in attendance for the landmark anniversary due to the novel coronavirus.
"And yet, Hiroshima recovered, becoming a symbol of peace".
He repeated what he said November 24 at the peace memorial: "The use of atomic energy for purposes of war is immoral, just as the possessing of nuclear weapons is immoral".
The bombing's survivors lamented the slow progress of nuclear disarmament and expressed anger over what they said was the Japanese government's reluctance to help and listen to those who suffered.
"I pledge here, in the city of Hiroshima, where people have been praying for eternal peace, that (Japan) will do everything it can for the realization of a world free of nuclear weapons and lasting peace", he said.
The Holy See was among the first countries to sign and ratify the United Nations nuclear prohibition treaty.
"Many survivors are offended by the prime minister of this country who does not sign the nuclear weapons prohibition treaty", said Keiko Ogura, 84, who survived the atomic bombing at age eight.