Trump's Iran war is reshaping US alliances from South Korea to the Middle East - analysis

The US has slammed European allies and allies such as South Korea. Threats to Oman show that the White House is willing to threaten partners and friends of the US.

On August 17 the homepage of the BBC had two important headlines that reflect changing US policy and the affect it is having on the world order.

“Trump threatens to bomb US ally Oman, if it ‘gets in the way’ over Iran deal” was the first headline. “Trump says to reduce military drills with South Korea after it stayed out of Iran war,” was the second.

The two headlines reflect a US policy that is now having a kind of butterfly affect around the world. The US and Israel chose to bomb Iran in later February 2026.

Now the US is reducing its role in the Pacific and Asia and pivoting to the Middle East. After a decade and a half where the US has sought to bolster its focus on China and Asia, the US strategy is now deeply focused on the Strait of Hormuz and US ties around the world are changing.

The US has slammed European allies and allies such as South Korea. Threats to Oman show that the White House is willing to threaten partners and friends of the US.

The US has been involved in Asia since the 19th century

The decision on South Korea could have long term ramifications. Along with the US using large numbers of munitions in the war on Iran, there is now a chance that US friends in both Europe and Asia may see the US as an increasingly erratic and uncertain friend. What are reports saying?

The Guardian in the UK noted that “South Korea’s president ⁠has renewed his push to regain independent control of the military from the US in the event of war and urged faster progress in acquiring nuclear-powered submarines after Donald Trump’s order to cut joint drills.”

The report added that “Lee Jae Myung said on Tuesday that Seoul should proceed without disruption with ‌the planned transfer, during his term, of ‌wartime operational control, or Opcon, of South Korean forces from the US – a goal he and the government have long held.”

“A strong alliance makes the foundation of security stronger, and strengthening our own capabilities increases our value and necessity as an ally,” Lee said. What this means is that South Korea may be thinking ahead. It’s not known yet how much the US decision could inform the next decade of US policy and how US allies and partners relate to each other and to Washington.

The current US security ties around the world often date from either the Cold War or earlier. It’s worth reviewing the hundreds of years of US policy in Asia. For more than 170 years, the US has viewed Asia and the Pacific as central to its long-term strategic interests. This goes back to the mid-1850s.

One of the earliest turning points came in 1853, when Commodore Matthew Perry sailed into Tokyo Bay with a squadron of US warships.

His mission was to persuade Japan to end centuries of isolation and open its ports to international trade. The resulting Treaty of Kanagawa marked the beginning of America's sustained role in East Asia and helped lay the foundation for Japan's modernization and its later emergence as a major regional power. The US was stepping in where European colonial powers had been before.

Japan, eager to learn from the US and others, began to modernize its military. Decades later it defeated the Russian navy at the battle of Tsushima. Japanese expansion in Korea and then China led to the decision by Japan to also attack the US in 1941.

The Japanese decision came after years of policy debate in Japan the discussed two different strategies: the Northern Expansion Doctrine (Hokushin-ron), favored by the Army to strike Soviet Siberia, and the Southern Expansion Doctrine (Nanshin-ron), favored by the Navy to head south toward Southeast Asia and Indonesia.

After the US role in Japan had long term ramifications, the US also engaged in other important efforts in Asia. During the Cold War, US strategy shifted from commerce to containment.

Following the Korean War, Washington sought to prevent the spread of communism across Asia. That policy culminated in the Korean and Vietnam wars, where hundreds of thousands of American troops fought. Consider the US Marines coming ashore in 1965 in Vietnam near Da Nang. Little did Washington know that the US would remain for almost a decade.

Another historic shift occurred in 1972, when US President Richard Nixon traveled to Beijing to meet China’s Chairman Mao Zedong. The visit altered the global balance of power.

This was the era of Détente and Trilateral diplomacy. By opening relations with China, the United States sought to exploit the split between Moscow and Beijing. Nixon's diplomacy transformed China from an isolated revolutionary state into an increasingly important player in the international system.

China eventually pursued a policy called “Hide your strength, bide your time" (taoguang yanghui). Deng Xiaoping in the late 1980s and then other leaders championed this. Now China is more assertive. Who would have known that Nixon’s visit might lead to this change. Who would have known that Perry arriving in Japan would have long term ramifications.

During and after the Cold War, the United States expanded its network of alliances with Japan, South Korea, Australia, the Philippines, Thailand, and other partners while maintaining a large naval presence across the Pacific. Now the US is shifting naval assets to the Middle East due to the Iran war.

While successive US administrations have emphasized the Indo-Pacific as the primary theater for long-term American strategy, there is now a sense that US policy is focused on the Middle East.

Some see this as important for the US-Israel relationship. In fact, some argue that Israel today is one of America’s only allies. However, the long term affect may be that other US partners and allies begin to seek new relationships and hedge their bets about the future.

US policy in Asia has shown historically that certain policy moves have long term affects. Reducing the US role with South Korea could be one of those moments.