If dialogue breaks down on Tuesday, that may indicate to U.S. and North Korean officials that diplomacy as a strategy has failed, leaving only military solutions on the table.
"Failure to reach any deal would almost certainly return the military option to the fore as the U.S. administration's preferred means of removing the North Korean threat," said the IISS note.
Others, however, maintain that the chance of conflict remains a distant possibility. Stangarone, for example, said a lack of a deal would likely "result in efforts to intensify economic pressure on the regime to bring it back to the table."
Ultimately, the majority of experts anticipate the summit to produce vague but general commitments to nuclear disarmament. That's "unlikely to have a big impact within Asia because those kinds of commitments are nothing new," Squassoni said.
Stangarone, for his part, said he expects the summit will produce only a general framework or declaration, but warned that it's the working definition of denuclearization that Asian powers will be looking for.