From the Executive Summary: "Today's terrorist landscape is more fluid and complex than ever. For this reason, counterterrorism remains a top priority for this Administration. Our principal terrorist enemies are radical Islamist terrorist groups that seek to conduct attacks globally, violate our borders, and radicalize and recruit potential extremists within the United States and abroad. We continue to face threats from Iran, the most prominent state sponsor of terrorism, through its global network of operatives and its ongoing support to an array of terrorist groups. Terrorists motivated by other forms of extremism also use violence to threaten the homeland and challenge United States interests. These terrorist threats are different in many ways, but they all seek to use violence to undermine the United States and disrupt the American way of life."
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