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Too often, military defense comes off as offense

The ‘security dilemma’ explains why maneuvers meant to protect peace can lead to war.

Members of the Philippine Coast Guard participated in a maritime exercise with Japan and the United States in the South China Sea in June.Veejay Villafranca/Bloomberg

After a historic summit at Camp David last month, the leaders of Japan, South Korea, and the United States vowed to defend themselves against China’s “dangerous and aggressive behavior.” China, however, took the new accord as a hostile act. “The US has become the biggest threat and challenge to regional peace and stability,” a Chinese government spokesperson asserted.

In the coming years, China and its partners will work intensely to strengthen their military power — only to counter American threats, of course. So will the United States and its partners — only to counter Chinese threats. Each side insists that it seeks only to defend itself. Neither believes the other, so both prepare for war. That makes war more likely.


Because this spiral of mistrust is so common, it has a name: the security dilemma. It tells us that steps one country takes to increase its security often provoke rivals to take countersteps. That leads to competition that makes all parties less secure.

“If you’ve taken a basic international relations class in college and didn’t learn about this concept,” the scholar Stephen Walt has written, “you may want to contact your registrar and ask for a refund.”

The US-China conflict is a sterling example of the security dilemma. Both sides behave like wounded innocents. They insist that they are building new weapons systems and deepening military alliances only to protect themselves against a predatory enemy. The Chinese navy says it is interested only in “coastal defense” and is simply “watching the house and guarding the courtyard.” Vice Admiral Karl Thomas, commander of the US Seventh Fleet, which operates near Chinese waters, sees the opposite. He commands a force of about 70 warships, 150 aircraft, and more than 27,000 sailors.

“You have to challenge people,” Admiral Thomas said in explaining his approach to China. “When they’re taking a little bit more and more and pushing you, you’ve got to push back.”


Which side started this cycle of fear, accusation, and hypermilitarization? No true answer is possible, because the two sides’ perspectives are so vastly different. Besides, it wouldn’t matter. The question of how the cycle began pales in significance beside the terrifying question of where it will end.

World War I erupted because of the same security dilemma. In the first years of the 20th century, Germany came to fear British sea power. It built new warships to defend itself against possible attack. Britain responded by massively increasing the size of its own navy. Both sides then built up their land forces. It took only a single spark — the assassination of Austria’s crown prince in Sarajevo — for that competition, seen by both sides as defensive, to erupt into a firestorm of global conflict.

A more recent example of the security dilemma at work is the Cuban Missile Crisis of 1962. A year before, the United States had sponsored an invasion of Cuba by its exiles. To deter a possible second invasion, Fidel Castro invited the Soviet Union to deploy nuclear missiles on the island. He and the Soviets may have seen the deployment as defensive, but the United States took it as a mortal threat. Discovery of the missiles set off a terrifying 13-day crisis that nearly led to nuclear war.

All countries seek to guarantee their security. The traditional way to do that is by building up armies and navies. Since this inevitably triggers counter-buildups, is there an alternative? Diplomacy is the obvious answer. But it runs against human emotion.


Diplomacy dictates that differences between countries should be resolved through negotiation and compromise. Human nature, however, makes it difficult for people to see the world from an adversary’s perspective. The Scottish poet Robert Burns wished that were not true: “O wad some Power the giftie gie us / To see oursels as ithers see us!” That “giftie” has not yet arrived. People instinctively believe that they see the world clearly and that other views are wrong. This fuels the security dilemma.

Some students of international relations argue that this syndrome is not inevitable and can be eased if world leaders work to avoid it. “The security dilemma is what the political actors want it to be,” the scholar Radomir Dolejsi has concluded, “and therefore can be overcome.” Yet today, world leaders show little will to overcome it.

Tensions in East Asia are rising to alarming levels. Both China and the United States believe that by militarizing the South China Sea and surrounding waters, they are only defending peace. The United States is resuming military maneuvers in South Korea that had been suspended because the previous South Korean president considered them too provocative. Meanwhile, North Korea responded to last month’s Camp David summit by announcing new ballistic missile tests.

After the summit, President Yoon Suk Yeol of South Korea said that the new accord binding his country to Japan and the United States “will help build a world that’s more peaceful.” North Korea saw just the opposite. It issued a statement warning that the accord means “thermonuclear war on the Korean peninsula will become more realistic.”


Both the US/Japan/South Korea side and the China/Russia/North Korea side say they seek peace through strength. Each feels threatened by the other and arms itself accordingly. The security dilemma is doing its pernicious work.

Stephen Kinzer is a senior fellow at the Watson Institute for International and Public Affairs at Brown University.