Leithart seems to be being careful not to directly call for Christians to risk their lives in confrontation with the state.  Perhaps it was, in light of the David Lane flap, an effort to assure everyone that he is not advocating something that sounds too much like he is inciting sedition.

In Greek, martyria means "witness," specifically witness in a court. At the very least, the decision challenges American Christians to continue to teach Christian sexual ethics without compromise or apology. But Windsor presents a call to martyrdom in a more specific sense. There will be a cost for speaking the truth, a cost in reputation, opportunity, and funds if not in freedoms. Scalia's reference to the pagan Roman claim that Christians are "enemies of mankind" was probably not fortuitous.

He concludes by drawing on biblical stories that mention separating wheat from chaff, and inserts an image that also evokes the Holocaust.

The only America that actually exists is one in which "marriage" includes same-sex couples and women have a Constitutional right to kill their babies. To be faithful, Christian witness must be witness against America.

God has his winnowing fork in his hand, and he's ready to use it. There's likely to be a lot of chaff, blown away like mist. But there will be a harvest. We're being sent into an oven, but Jesus will crush the grain of the harvest so that, baked in the fire of the Spirit, it will become bread for the life of the world. [emphasis added]

In the introduction to Between Babel and Beast, Leithart's meaning was plain.  He wrote that Christians must respond to what he calls the heresy of "Americanism" -- to which he observes that too many of his fellow conservative Christians have conflated with Christianity itself.  He believes the correct response is for martyrdom in two senses of the term.  "Churches must repent of our Americanism," he wrote, "and begin to cultivate martyrs -- believers who are martyrs in the original sense of "witness" and in the later sense of men and women ready to follow the Lamb all the way to an imperial cross."

It is worth noting that David Lane did not back off from his call for Christians to wage war and create martyrs. He just took his essay down. (It seems likely that his political clients, such as Sen. Rand Paul, probably saw his essay as a potential obstacle to their electoral ambitions.)  Peter Leithart, the former Senior Fellow of Theology and Literature at New St. Andrews College in Moscow Idaho, and current director of the new Trinity House Institute in Birmingham, AL, has apparently also not changed his views between his book of last year and his blog post of last week.  He clearly believes that martyrdom is what is required -- and that horrific confrontation lies ahead.