The United States sent 2 million troops to war, but in the end, Osama bin Laden was killed by 23 American commandos acting on intelligence provided by the CIA. And bin Laden was killed in Pakistan, where troops were not sent in large numbers. Nineteen men attacked America on 9/11. Twenty-three Americans killed bin Laden. But in between, more than 6,000 troops would die and well over $1 trillion spent.