With the 20-year anniversary of the 9/11 attacks approaching, a long-simmering debate that began in their aftermath about fencing around the Capitol building is getting new life in the wake of the Jan. 6 siege.

The proposal has never gone into effect largely because lawmakers have insisted on keeping public access to the legislative branch’s seat. But the Capitol siege, in which five people were killed, including a U.S. Capitol Police officer, is forcing a reconsideration of that notion.