Same as any other time. Say your prayers, study the scriptures, keep close to Christian fellowship (especially at the Eucharist), hold the whole situation up before the God who groans with the pain of the world (Romans 8) and has promised to wipe away all tears from all eyes (Revelation 21). War sharpens some of the horrible things about the way the world currently is but doesn't change the basic structure of a good world in rebellion and longing for redemption -- with humans caught up in the middle of it all.

There is a peculiar aspect to contemporary war because of broadcasting and so on; people can become voyeurs, captivated by scenes of suffering and devastation while they sit in comfortable homes drinking coffee or beer in front of the TV. Like all voyeurism, this can deaden genuine human reactions and give a quite unhealthy sense of false involvement which then breeds the wrong sort of detachment as its reverse. Enough to find out basically what's going on, pray about it, and get on with your real work and the rest of your life.

The idea that wartime somehow suspended all normal human life was undermined two generations ago by a splendid essay by C. S. Lewis entitled "On Learning in Wartime." It's in one of his volumes of collected essays somewhere.