A black-and-white targeting screen offers the only view of the road ahead. It is a quagmire - there are few obstacles as fiendish, or varied, as Ukrainian mud. One moment it"s a deep, sucking soup, the next a thick putty clogging machinery, weighing down boots, and gumming up everything. We drive past one soldier who is hammering frozen chunks of it off his stranded truck with a mallet.