According to Bonhoeffer the pastor who took part in an assassination plot against Hitler, Riverside was far gone as a church in the 30s preaching politics rather than the Gospel of Christ. The Union Seminary in town was as well.
It is not certain Dietrich Bonhoeffer did that. If he did, then he conspired to commit murder - not the best way to emulate Christ, but a way to impress leftist pseudo-theologians.
Marc Thiessen wrote a book purporting to disprove that theory about Bonhoeffer.