Vandalized public monuments stayed decayed for decades until Moses restored them.

Evidence

Rare was the New Yorker who could remember when the Columbus Circle monument to the men who died in the explosion of the U.S.S. Maine in Havana Harbor had not been dingy, or when the boy standing in the prow of the monument’s bow had possessed a wreath, or, for that matter, hands to hold it with. As soon as Moses had taken office, he had surrounded the monument with scaffolding and concealed it with drop cloths. Now the scaffolding and drop cloths were removed and the boy had his hands back, and a wreath was in them—and the entire huge monument behind him had been scrubbed clean and white. — Robert A. Caro, The Power Broker, 1644