You nailed it brother. I'm not a government employee, but for the time being, I'm forced to work in their facility. I do have my own Macbook here which I use for all my scripting/data analysis/etc, but I have to leave the building to get to WiFi. It is infuriating that these idiots have been fooled into thinking that they are more secure by using IE8 over.... anything else.
"The government" doesn't mean that. My wife works for the DOI and their entire bureau uses Chrome and their government email and other services are managed through Google Apps, her cubical contains a typical locked-down Windows PC and a Red Hat workstation, the workstation runs Chrome and FF which are only as behind the curve as far as the stable releases are. I knew some guys who worked for NOAA as contractors who said they were pretty modernized as an agency too (running modern web servers on Python, vs the gigantic legacy J2EE apps I maintained during my stint as a government contractor).
The agencies you mentioned are less than a hundredth the size of the agencies in the US Gov which are using IE8. The smaller agencies have the luck of getting to be forward thinking. The rest are crushed down by bureaucratic inertia and Microsoft development cultures (with some of the J2EE thrown in too). The IE8 stuff is mainly because they have built so many shitty .NET apps that won't work properly without IE.
Fair enough, there are plenty of organizations both inside and outside the government that have sane technology standards that contradict my cheap generalizations.