Final answer:
George W. Bush and Three Mile Island nuclear power plant are the key terms for this question about the 43rd US president and a nuclear power plant accident.
Step-by-step explanation:
George W. Bush is the key term that fits the first definition. As the 43rd president of the United States and former governor of Texas, he responded to the September 11, 2001 attacks by sending troops into Afghanistan and Iraq.
For the second definition, the Three Mile Island nuclear power plant in Pennsylvania is the key term that caused public fear and opposition to further development of nuclear power plants after a partial meltdown accident in 1979.
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