It's  United Nations Space Command.  Not Special Corps!  

And most people Think John is a marine because most don't think that the Navy really Have ground force at all.  All they see is big ships and sweet jets about.  I got into a big arguement with a Marine about navy's ground units. 

Navy's Mobile Combat units 

-CB's  Contruction Battalion,

-EOD  Explosives Ordnance Disposal

-Seals  Self explanitory

-SWWk  Seal support

-Sand Sailer Army trained Sailors that help both Army and Marine battalions.

It may not look like a lot, but there are quite a bit of mobile units under those names as well.   I did work with EOD mobile unit 17 for a little bit, it was the time of my life doing so.  But I'm not quite up for physical standards to stay with them unfortunately. The Marines my have more units, but the navy have a few of their own.