Is Constantinianism all bad?

"Constantinian" has lately been a favored pejorative in
theological circles. The term--an allusion to the fourth-century Roman emperor
whose conversion to Christianity turned a marginal sect into a state religion--has
been used to deplore any alliance between the church and the state or, more
broadly, between the church and the dominant political culture.

Thanks to the influence of John Howard Yoder and
Stanley Hauerwas, among others, anti-Constantinianism has provided an edge of
energy to much mainline preaching and theology and has fueled a healthy
suspicion about ways that churches can lose their identity by aligning
themselves with power or the mindset of modernity.

But is Constantinianism entirely wrongheaded? Don't
Christians want people in power to embrace Christianity and Christian values?
Is it a bad thing if they do? Is it impossible or meaningless for them to try?

Oliver O'Donovan in The Desire of the Nations offered, in direct
conversation with Hauerwas, a learned defense of the idea of "Christendom," or
Constantinianism. O'Donovan's writing is dense and his arguments elliptical,
however, and my sense is that his book hasn't made much impact on the
conversation, at least not outside graduate schools.

Peter Leithart's Defending Constantine has also deepened the discussion, both about
what Constantine actually did and about the reputed perils of Constantinianism.
That Hauerwas himself (reviewing the book for the Century) finds Leithart persuasive on a number of points suggests
that battle between Constantinians and anti-Constantinians is not the
black-and-white contest that popular theology often suggests it is.

The Journal
of Lutheran Ethics has extended this important discussion with Timothy
Furry's critical summary of Leithart and Leithart's reply. Furry, like
Hauerwas, notes that the debate over Constantine involves both historical and
theological issues, which can be distinguished, even if they can't be fully
disentangled. Was the church pacifist before Constantine? Did Constantine's
faith reshape the empire as well as revise the church? Does that matter for how
we evaluate Constaninianism?

Leithart concludes that Christians can't reject
out of hand the idea of a Christian civilization and a Christian political
order--unless they believe that the world is impervious to the gospel.