AMSTERDAM — Nuclear terrorism is officially the main topic for world leaders at a two-day summit in the Netherlands starting Monday. In practice, the Ukraine crisis will likely overshadow those talks.
The Nuclear Security Summit in the Hague will form the backdrop for an emergency meeting of Group of Seven leaders on Russia's annexation of Crimea. It's a confrontation between Russia and the West reminiscent of the Cold War.
Russian President Vladimir Putin is not attending, instead sending Foreign Minister Sergey Lavrov, who is expected to hold talks with U.S. Secretary of State John Kerry.
But experts say frantic diplomacy focused on Ukraine shouldn't divert from the goal of better security of nuclear material.
"International attention can turn in a moment," said Deepti Choubey, a senior director at the non-government Nuclear Threat Initiative. "The attentions of terrorists do not."
Delegations from 53 countries, including the leaders of the U.S., China and Japan, have started to arrive in the Hague. They will meet to negotiate on reducing and securing supplies, and keeping them out of terrorists' hands. The G-7 includes the U.S., Britain, Germany, Japan, France, Italy and Canada.
Notable absentees from the summit are North Korea and Iran, excluded by mutual consent.
The summit is the third since US President Barack Obama launched the series in 2009 shortly after taking office, saying that reducing the risk of a terrorist attack with either a nuclear weapon or a "dirty bomb" was one of his most important international policy goals.
Because countries usually regard protecting nuclear weapons and facilities as a confidential sovereign matter, the summits center on individual commitments by participants and conclude with a non-binding accord.
Still, they already have reached tangible results.
The number of countries that possess enough highly enriched uranium or plutonium to make a bomb has fallen steadily, from 39 before the first conference in Washington in 2010 to 25 at the start of the Hague summit.
And while Ukraine is likely to dominate diplomacy behind the scenes in The Hague, it already is a nuclear success story.
The country voluntarily gave the nuclear weapons housed on its soil back to Russia after the collapse of the Soviet Union and following through on a 2010 summit promise, has recently disposed of its remaining stock of around 176 pounds of highly enriched uranium.
Deepti Choubey, a senior director at the non-government Nuclear Threat Initiative, said that fact underlines the importance of the process.
"How much more concerned would the world be today (about the crisis in Ukraine) if that material were still there?" she said.