Not since the Vietnam War has a foreign policy issue transformed Western domestic politics in the way the threat from Islamic State has. Neither the attacks of Sept. 11, 2001, nor the subsequent wars in Afghanistan and Iraq — however costly and corrosive of national purpose — so profoundly reset the playing field of politics.
Across the West, domestic policy debates — ranging from immigration to law enforcement to education — are now refracted through the lens of the new terrorism. Because of the Islamic State-related attacks in the United States and Europe, the line between foreign and domestic policy is gradually being erased.
Distinctions of left versus right or liberal versus conservative now obscure rather than illuminate the policy decisions confronting governments. Today, an anti-immigrant policy can just as easily emerge from the political far left as from the far right.