Within a month, the US military was on the ground in Afghanistan. Within three years the US had an official report on the causes of the events of 9/11; the well-resourced expert commission that produced it identified the weaknesses of America’s national-security agencies and provided recommendations for addressing them.
2001年，9·11恐怖袭击后不久，美国出台了大规模的新安全措施，在全国机场内生效。一个月内，美军就登上了阿富汗的领土。三年内，美国出台了9·11起因的正式报告，专家委员会在动用了充足的人力物力进行调研后指出了美国国家安全机构的弱点，并给出了如何改进的建议。