I agree, but one has to be careful in definitions here. Evil in the Judeo/Christian tradition is defined as nothing but a perversion of good, or flawed good. This was first widely elucidated by St. Augustine. In other dualistic traditions--where they see evil and good in eternal struggle--evil has substance in itself.
The reason its important to define evil as perverted good, is that it reflects reality--every person has SOME partial good in them....and that doesn't contradict the idea that "Man is not inherently good" for we've already defined evil as "partially" good in that evil is perverted or twisted good.
I'm not sure, but a Moslem may agree with our definition of evil--the difference is (both with Jews & Moslems) they will say, by one's own unaided efforts you can become good, or at least better. Christianity though, has always said, that short of the empowerment of the grace of God (through Jesus & His work on the Cross) no one can ultimately do good--we are stuck in our "perverted or partial good" (or evil) ways.
The danger of Islam, if I read this article right, is that (like the secular ideologies of Marxism and Fascism) it is utopian--namely that through external means--a shari'a theocracy, people can be MADE good.
This is foolishness and more... Far more people have died to usher in "utopian" societies than the worst of less noble motivations.