Seventy-three years after the 1945 atomic bombings of Hiroshima and Nagasaki, which took more than 200,000 lives by the end of that year, we are no closer to a world without nuclear weapons. Pledges to achieve that goal, which Japan has advocated for decades, were repeated in ceremonies held over the past week to mark the anniversaries of the U.S. atomic bombings of the two cities in the closing days of World War II. But more than seven decades later, we can hardly say that a path has been laid out to eliminate nuclear arms.

Last year, a landmark treaty prohibiting nuclear weapons was adopted at the United Nations. But without the participation of nuclear weapons powers as well as countries that rely on the "nuclear umbrella" of their allies, including Japan, there is little prospect that the treaty would effectively pave the way for disarmament. Today, more than 14,000 nuclear warheads exist in the world.

Former U.S. President Barack Obama, whose call for a "world free of nuclear weapons" in his Prague speech earned him the 2009 Nobel Peace Prize, became two years ago the first sitting U.S. president to visit Hiroshima. The U.S. strategy for nuclear weapons, however, did not undergo substantial changes during the Obama presidency. And his successor, Donald Trump, released a Nuclear Posture Review in February that promoted the use of smaller nuclear weapons that would be easier to use, and did not rule out pre-emptive nuclear attacks in order to protect the interests of the U.S. and its allies. Tokyo said it "highly appreciates" the new U.S. strategy in that it clarifies Washington's commitment to providing extended deterrence to its allies.