The "evangelicalism" people talk about on Twitter doesn't exist.

People talk about it like it is a monolithic, cohesive network, with discernible and clear leaders, doctrine, culture, etc. But it is none of those things.

It is a loosely—if at all—connected movement of Christians born of the Protestant Reformation and the Great Awakening.

Its most authoritative scholarly definition cites (1) the centrality of the Bible, (2) the centrality of the cross, (3) the necessity of personal conversion, and (4) an emphasis on activism/evangelism as its defining characteristics. (see "Bebbington Quadrilateral")

Being a loosely connected movement defined merely by those four markers means evangelicalism is a huge tent, and has always contained differences of opinion on things like the scope of the church's mission, charismatic gifts, politics, and more.

The way some Christians talk about it reminds me of the way some talk about "the culture"—like some clearly defined thing "out there," separate from me. But if you are a child of the Reformation + Great Awakening and are defined by the four markers above, you are an evangelical.

That doesn't, of course, mean there is never warrant for criticism of "evangelicalism," but it should take these points in mind, it should be more specific, and it should be offered as humble, self-reflective criticism, not grenade lobbing.

Essential reading on this topic: George Marsden's "Understanding Fundamentalism and Evangelicalism" and "Religion & American Culture," and Thomas Kidd's "The Great Awakening" and "Who Is an Evangelical?"