Why does a private company host the US National Security Agency Homepage?

Why is the NSA website hosted by a private firm? A lookup of www.nsa.gov shows that it is hosted by: LINGUALISTEK 9861 Broken Land Parkway Suite 300 Columbia MD US 21046.

Lingualistek states that their mission and philosophy is:

"Linking State-of-the-Art Software Solutions with Languages Worldwide"

Lingualistek's own corporate webpage is hosted by interland. Why is a private company hosting the NSA .gov page on their own netblock? Lingualistek is not a hosting company, and does not host any other pages, not even their own. A google search of the Lingualistek web page for NSA reveals a single reference, in a job description.

Other US gov't sites:

whitehouse.gov - akamai
CIA.gov - CIA netblock
DIA.mil - DOD netblock
Army.mil - Army Netblock

Interesting.