Time and manpower bottlenecks are really the biggest sticking points for the Federation; sure they can pull a ship into drydock, strip out all the amenities and science doodads, drop in enough shield generators, phaser banks, and torpedo launchers to make even a hardened veteran from the 4-year war grunt in approval, and do so in three weeks, but that's time and manpower dependant, as well as ... More @Wikipedia
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