Matthew Gertken, geopolitical analyst at Stratfor, a global intelligence company, said the summit did little to move toward securing nuclear materials.

"We don't think this summit amounted to much other than an attempt to emphasize Obama's commitment to the international process," he said.

And while the agreement to secure nuclear materials by 2014 is necessary, there is no guarantee that will happen, he said.

Gertken said an effective agreement would mean an agreement of nations not signed onto the Non-Proliferation Treaty to start giving up their nuclear weapons. He added that Stratfor advocates no policy positions.

Still, other experts said the summit was a step in the right direction.

"This is a president who reads the diplomatic environment very sharply," said Matthew Rojansky, deputy director of the Russia and Eurasia program at the Carnegie Endowment for International Peace.

The Bush administration, by contrast, established a number of new coalitions and institutions that ended up competing with existing institutions.

"On a political level, that sent the wrong message, and Obama is doing the opposite," he said.

Justin Logan, associate director of foreign policy studies at the Cato Institute think thank, said the president wanted to get other nations on board to take action toward securing fissile material and broaden the discussion on nuclear weapons after the Nuclear Posture Review and the new Strategic Arms Reduction Treaty (START) with Russia.

Scott Payne, policy advisor for national security at the Third Way think tank, called the summit a success, citing the U.S.-Russia Agreement to reduce nuclear material as a powerful example.

While the summit concluded in an unspectacular manner, it was a step forward. Payne said more such steps are likely to follow.