Jason X35:They do (they're called Shiva Nukes) but I think they don't use them as much because they realize the damage they cause. Even if they destroy their enemy the EMP blast will destroy some of their tech...so they just decide not to use them. Remember, in the future they rely heavily on their technology. But yes, I get your point.
Or the SHIVA would have done jack ***. Even with the ships docked together, there would still be individual shielding systems-the corvette and the supercarrier-and it wouldn't have done much damage.
For example: http://www.youtube.com/watch?v=FuAkvJxAYLg 1:13. Subspace rupture + strongest shields ever known [for that particular canon]=pwned. Similar to the slipspace bomb in Halo Reach.
Just to put it in perspective: http://www.youtube.com/watch?v=lVgQs-t7VVw&feature=related. Yeah.
Supreme Commander Matt Klassen, captain of the Devastator
-class ship Enlightened
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