Final answer:
U.S. intelligence became aware of Osama bin Laden in the late 1990s when he was indicted for his involvement in embassy bombings.
Step-by-step explanation:
U.S. intelligence became aware of Osama bin Laden in the late 1990s. In 1998, bin Laden became widely known to U.S. intelligence when he was indicted by the United States for his involvement in the bombings of U.S. embassies in Kenya and Tanzania. After these attacks, bin Laden became a prominent target for U.S. intelligence efforts.
Learn more about U.S. intelligence awareness of Osama bin Laden