海南封关东南亚跳脚？洪森家族集体倒向美国，越南建高铁找德韩

Group 1 - Hainan's customs closure, effective December 18, 2025, marks a significant step in China's high-level opening, allowing free movement of goods with zero tariffs for imports and a 15% corporate and individual income tax rate, lower than many surrounding regions [4] - Southeast Asian countries, particularly Cambodia and Vietnam, are reacting to Hainan's new status as a processing hub, which could challenge their agricultural exports to China, necessitating improvements in their own industries to avoid becoming mere raw material suppliers [4][6] - Cambodia's Prime Minister Hun Manet is balancing relations between China and the U.S., having recently signed a trade agreement with Trump to lower tariffs on U.S. goods, indicating a shift in strategy amidst increasing U.S.-China tensions [6][8] Group 2 - The construction of the Cambodia-China railway project has faced disputes over equity control, with Cambodia seeking to change the ownership structure, reflecting a desire for greater independence while still relying on Chinese investment [8] - Vietnam's decision to partner with Siemens and local firms for its high-speed rail project, bypassing Chinese involvement, illustrates a strategic pivot in infrastructure development, driven by concerns over dependency on China [8][11] - The dynamics of Southeast Asia's economic relationships are shifting, with Vietnam's reliance on Chinese economic ties and U.S. security assurances becoming increasingly complex, especially in light of Hainan's new trade policies [9][13]