SEOUL — South Korea has applied to join the Comprehensive and Progressive Agreement for Trans-Pacific Partnership, a twelve-member economic and trade pact. The application advances after years of internal discussion in Seoul about membership in the bloc.

Washington's trade policies and the economic consequences of the U.S.-Israeli war on Iran have raised the cost of close alignment with the United States and weakened confidence in U.S. commitments. Seoul's options short of rupture include joining regional trade frameworks, arming Ukraine directly, and pursuing its own diplomacy with Iran on energy shipments.

The CPTPP offers a framework for addressing traditional trade markets, supply chain cooperation, digital trade, and state-owned enterprises. Its members include Australia, Canada, Japan, and the United Kingdom.

"For Korea, a mid-sized trading nation, survival now depends on diversifying markets and stabilizing supply chains. The CPTPP offers a network well suited to those goals," said Choi Kang, President of the Asan Institute for Policy Studies.

Bruce Klingner, a long-time Korea watcher, described strain in the bilateral relationship between Seoul and Washington. "While the biggest threat to the alliance remains North Korea, the biggest challenge to the alliance now comes from the United States," he said.

Klingner also pointed to recent trade negotiations between the two countries. "Having bullied Seoul into a disadvantageous trade deal that violated the US-South Korea free trade agreement and the US Constitution, the Trump administration is demanding more – and promising less to its security and economic partners," he said. He added: "The United States may have degraded military deterrence by undermining the perception – in the minds of both allies and opponents – that Washington is a dependable security partner."

Japan's posture toward South Korean membership has shifted over time, according to Michael Beeman, former Assistant US Trade Representative for Japan, Korea and APEC. "Earlier this decade, Japan had given South Korea its very cold shoulder on entry," he said. "Kishida-era warming in Japan-ROK ties seemed to have turned that around."

A recent joint statement following the meeting between South Korean President Lee Jae Myung and Japanese Prime Minister Sanae Takaichi indicated Japanese support for South Korea's CPTPP membership. "I don't sense Japan's posture is any longer a top obstacle," Beeman said.