American Evangelicalism is not the guardian of Christianity and Christian Orthodoxy, and being an Evangelical does not necessarily mean one is a follower of Christ. Christendom transcends the politics and practices of American tribal Christianity.
I distinguish two branches of American Evangelicalism: one is cultural, the other is theological. For example, cultural evangelicalism is an ideological group that interprets the Christian faith through the lens of American patriotism and politics, American exceptionalism and American supremacy, and American hegemony in the world. Cultural Evangelicalism is quite a political phenomenon which sustains American Christianity and the American way of life and through the American dream ideology.
On the other, for many critics, American Evangelicalism is race-oriented and conscious; generally, it is linked to whiteness or White Christianity—whether it is cultural evangelicalism or theological evangelicalism–, which is very problematic for American Christianity and the public witness of Christianity in the American society. A possible solution to the crisis of American Evangelicalism is to deculturalize, depoliticize, and deracialize the Christian faith in the American culture.
Let me add one more note. Some genuine Christians do not identify themeselves as evangelicals; being outside of the Evangelical spectrum does not make one less a Christian. (It’s like a Christian who embraces Calvinism versus another who subscribes to the tenets of Arminianism. Maybe, that’s not the best example to give.) Honestly, I don’t do well with theological and political labels.