A growing number of Americans are reluctant to use US troops to defend South Korea from a North Korean invasion, according to a recent survey by the Chicago Council on Global Affairs, a nongovernmental research institute. The survey, conducted from Sept. 7-18 among 3,242 US adults, shows that only half of the respondents agreed with the idea of committing US troops to defend South Korea, marking a significant decrease from the previous year, when 63 percent were in favor.

The shift in public opinion comes amid heightened geopolitical uncertainties, underscored by Russia’s invasion of Ukraine, and reflects a growing partisan divide in the United States over foreign military intervention. Republicans, who have historically supported a US military presence overseas, now exhibit a pronounced opposition, with less than a majority (46 percent) backing the defense of South Korea.

By contrast, European conflicts were shown to command more American support. The survey found 57 percent of Americans would support the use of US troops if Russia invades a NATO ally like Latvia, Lithuania or Estonia, and 64 percent if Germany faced invasion, indicating a geographic bias in Americans’ willingness to intervene.

Support for US military bases in East Asia was shown to be similarly in decline, with 64 percent supporting long-term bases in South Korea and 63 percent in Japan -- a decrease of 6 and 4 percentage points, respectively. Again, the drop was markedly steeper among Republicans, aligning with the “America First” ethos propagated by former President Donald Trump, who criticized transnational alliances and repeatedly accused South Korea of freeloading off of the US' military support.

As the 2024 US presidential election looms with Trump far ahead of other Republican presidential candidates in polls, a resurgence of such isolationist foreign policies remains a real possibility in the near future.

Currently, 28,000 US service members are stationed in the Korean Peninsula under the 1953 South Korea-US Mutual Defense Treaty. However, unlike NATO, this treaty lacks a collective defense principle, leaving the extent of US intervention in potential conflicts ambiguous.

South Korea’s Yoon Seok Yeol administration has sought to strengthen military ties with the US of late in the face of threats from nuclear-armed North Korea. Maintaining the country’s alliance with the US remains popular, with a recent Gallup Korea poll indicating that over half of South Koreans support stronger ties.