He also said the next U.S. administration would maintain a strong commitment to Asia and the rest of the world, no matter what political party won the fall election.
The speech focused heavily on Asia, with subtle calls for China to work more amiably and fairly with other Pacific nations. It was when Gates discussed Myanmar that he was the most emotional.
"We have reached out, frankly, to Myanmar multiple times during this crisis in very direct ways," the Pentagon chief said. "It's not been us that have been deaf and dumb in response to the pleas of the international community, but the government of Myanmar. We have reached out, they have kept their hands in their pockets."
He said the government's obstruction of international efforts has cost "tens of thousands of lives."
U.S., British and French Navy ships off the coast of Myanmar are poised to leave because the government has blocked them from delivering assistance. Gates said the U.S. will not bring in supplies by force without permission of the government and will continue to "respect the sovereignty" of Myanmar.
The growing displeasure with the Myanmar government was clear at the conference, coming up in nearly all conversations among leaders. Gates met with his top Pacific commander Saturday to discuss the possible U.S. Navy pullout; a final decision has not been made.
In the speech, Gates said the next U.S. president will inherit the worrisome issue of North Korea's nuclear ambitions but will continue America's commitment to Asia.
While he said he could not make specific policy predictions for the next administration, Gates said there will be "no change in our drive to temper North Korea's ambitions, a policy not possible without China's valued cooperation."
Despite the often divergent views of the Republican and Democratic candidates, Gates said he is confident that the strong U.S. ties to Asia will continue regardless of who wins in November.
When a questioner suggested that the U.S. may not have the time, money or energy to maintain interest in Asia, he quoted former President Ford, saying, "We ought to be able to walk and chew gum at the same time."
On China, Gates extended a hand while also offering a subtle but somber warning.
Gates noted improved relations with the communist power. He said leaders have begun discussions on issues to "help us understand one another better and to avoid possible misunderstanding."
A long-sought direct telephone link between the U.S. and China has been established, and Gates said he used it recently to speak with the defense minister.
Yet Gates took unmistakable jabs without mentioning China by name. For example, he urged greater openness about military modernization in Asia.
In recent annual reports, the Pentagon has criticized China for its massive military buildup, saying its motives and spending are unclear.
"We desire to work with every country in Asia to deepen our understanding of their military and defense finances, and to do so on a reciprocal basis," Gates said.
Lack of such clarity, Gates said, can lead to outright suspicion.
In response, the top ranking Chinese official at the forum took aim at U.S. missile defense policies - which include plans for anti-missile defenses with Japan, as well as the deployment of missile defense sites in Poland and the Czech Republic.
Lt. Gen. Ma Xiaotian, deputy chief of the General Staff for the People's Liberation Army, said developing such an offensive - rather than purely defensive - system could tip the balance of power and threaten peace.
"We do not support either side to take the initiative to break the balance," he said. He also dismissed claims that China's military is dramatically expanding.
Gates' next stops were in Thailand and South Korea.
