Kahn on martyrdom's threat to the state

From Paul Kahn's "Putting Liberalism in Its Place" (link): 

The Western state actually exists under the very real
threat of Christian martyrdom:  a threat
to expose the state and its claim to power as nothing at all.  In the end, sacrifice is always stronger than
murder.  The martyr wields a power to
defeat his murderer, which cannot be answered on the field of battle.