As we mark the 25th anniversary of the Sept. 11 attacks, it is difficult to commemorate the gravity of that day without confronting what is happening in America today. Parts of our political culture have become increasingly comfortable rationalizing political violence and the deliberate murder of civilians.

If Osama bin Laden were alive, I suspect he would be thrilled by the direction in which America is heading. His strategy depended, in part, on exploiting the vulnerabilities inherent in an open society: its divisions, its freedoms, its capacity for self-criticism, and, ultimately, its willingness to turn that criticism inward. Bin Laden understood that America did not have to be conquered to be weakened. Americans could instead be exhausted, divided, and persuaded to lose confidence in the liberal democratic order he despised.