不错，快读到底了。但这句语义挺清楚的，语法就错了一个字，“他们提供*了*关键原料”。“他们为......提供了不可或缺的帮助”可

“他们为......提供了不可或缺的帮助”可能好一点

原文：

But elites still matter in a democracy. They matter not because they are democracy’s enemy but because they provide the critical ingredient to save democracy from itself.