heavy cruisers USS Salt Lake City (CA-25), USS Pensacola (CA-24) and USS New Orleans (CA-32) (listed from left to right) nested together at Pearl Harbor, 31 October 1943. Ford Island is at the left, with the battleship USS Oklahoma (BB-37) under salvage at the extreme left, just beyond Salt Lake City's forward superstructure. Note the radar antennas, gun directors and 8-inch guns on these three heavy cruisers. Two New Mexico-class battleships are visible in the background between Pensacola and New Orleans.
The Treaty cruisers were built to stay within the 10,000 ton limit and were quite limited as a result. For example, Japanese heavy cruisers, like Ashigara, is now rated as 17,000 tons. Also, there was a difference of doctrine. US cruisers were designed for long range action, while the IJN designed for night fighting.
"These things must be done delicately-- or you hurt the spell." - The Wicked Witch of the West.
"We've got the torpedo damage temporarily shored up, the fires out and soon will have the ship back on an even keel. But I would suggest, sir, that if you have to take any more torpedoes, you take 'em on the starboard side." Pops Healy, DCA USS Lexington.