The missile compares the ground with information stored in its
memory As the missile approaches its target, the final and most
accurate guidance system takes over. Digital Scene Matching Area
Correlation (DSMAC) compares what it can see on the ground with
a digital rendition of its target. This technology is
complicated and expensive but has been shown to work. But it is
only as good as the intelligence that underpins it. It will
never stop a missile hitting a long-abandoned target building or
a civilian shelter if the targeting information is not up to
date.