特朗普下令重启核试验，美官员称暂不含核爆炸

Group 1 - The core viewpoint of the article is that the U.S. government, through Energy Secretary Chris Wright, clarified that the recent directive from President Trump to restart nuclear weapons testing does not involve nuclear explosions but rather "system tests" [1] - The last underground nuclear test conducted by the U.S. was in 1992, and the Comprehensive Nuclear-Test-Ban Treaty (CTBT) was adopted by the UN General Assembly in 1996, which commits signatories to cease nuclear weapon tests permanently [2]