Intelligence agencies and the military often rely on the commercial imaging satellites owned and operated by Geoeye and DigitalGlobe.
To help plan tsunami relief and nuclear response operations in Japan the US government has almost certainly commissioned images from them.
The folks at Geoeye sent us images of some of the worst hit areas and the Fukushima nuclear complex that were combined using Google Earth.
The analysts at the National Geospatial Intelligence Agency and with the Japanese government are doubtless poring over similar images.
As Uyen Dinh, Vice President for Government Affairs at Geoeye put it in an email: "You'll see incredible destruction particularly at Fujutseka and Noriaga---entire forests have disappeared as well as half an island in the middle of the river."
Just move your mouse over the pictures to see the before and after images.