Re: Don't have capability/intention to match China force for force: Na
I want THOSE
Too many eggs in one basket. I remember talking to a retired USN rear admiral who taught military history; he explained that the cost to fill a single VLS with a missile (or quad-packed SAM) was about $2M, so a boat packed with 250 missiles would risk half a billion dollars of ammunition in a larger radar signature. It made more sense to spread all that ordnance across a number of smaller destroyers, each packing sensor suites just as powerful as the larger CG, but with smaller radar signatures and more tactical flexibility (to spread out, pincer, flank, etc.)
The only real advantage an arsenal ship like that would have is more relative fuel efficiency than a number of smaller craft, especially if it was nuclear powered, but a nuclear reactor would simply make it even more expensive than even three or four equivalent destroyers. Finally, the US has been building Burkes for years now, so building additional Burke Flight IIAs (and possibly IIBs) means declining unit costs and economies of scale.
EDIT: To quote my notes from our conversation
The reason you want a bigger ship is not because you want more firepower, it's to fit a bigger sensor and jammer suite. Past a certain point, sensor power doesn't scale up fast enough to justify the increased displacement.
Presumably, he was referring to the fact that a linear increase in sensor power requires a linear increase in displacement, but only increases the square root of the detection range.