Using Google cache to view blocked (by server) pages

The US military has an project called JRAC (Joint Rapid Airfield Construction) that has some of our gear as part of the solution. Recently a US colleague emailed a URL to read the blog posts of the current trial in Australia.

But the page will not load from New Zealand, so off to Google to view them in the cache, just make sure you click the cached links,

Google jracblog search

then click the cached text link, otherwise you have to wait for the picture requests to timeout..

Google Seach click the cached

So the bigger question is, why can’t I view the blog, and if it’s because the military want to “keep it secret” isn’t Google side stepping that via the cache? Or have the military not heard of robots.txt?