Comprehension of the history of cruisers as shown in these lists requires some understanding of the unique role (sharing both independent and combined fleet operations) that cruisers were expected to support in the US fleet, and of the consequent influence this role had on design.

[5] Since the cruiser nomenclature predates the hull numbering system, and there were several confusing renumberings and renamings,[6] there are multiple entries on these lists referring to the same physical ship.

Combat history summaries (wars and battle stars[7]) are listed only for the specific hull classification and number; for example, the World War II battle stars for a heavy cruiser (CA) and the Vietnam War battle stars for the same ship after its conversion to a guided missile cruiser (CG) are listed separately in each ship type list.

CA-1, CA-6 and CA-10 were never used, as ACR-1 Maine, ACR-6 California/San Diego and ACR-10 Tennessee/Memphis were lost prior to the 1920 redesignation, and their sisters' original hull numbers were carried over.

CA-20 through CA-23 were skipped with the merger of the CA and CL sequences, which allowed the reclassification of the Washington Treaty CLs as CAs without re-numbering.

that the DDG-993 Kidd-class guided missile destroyers, which were essentially identically armed to the Virginia-class cruisers, should have been redesignated CG-43 through −46.)

The first three modern cruisers in the Navy, the Atlanta, Boston, and Chicago, were most successful as technology demonstrators that stimulated the US industrial base, with features such as steel hulls and electricity generation.

The last two protected cruisers which initially served without hull classification numbers, the New Orleans and Albany, were purchased from a British builder during mobilization for the 1898 Spanish–American War.

[8] New Orleans class Beginning in 1891 Congress subsidized a number of fast ocean liners with plans to requisition them in wartime.

Unofficially, top naval officers initially referred to these ships as battleships because they cost almost as much, shared many features with them, and were intended to accompany them in fleet actions; they took care to ensure that Congress never heard their opinion.

[13] Chester class Omaha class The United States laid down its only six battlecruisers as part of the 1917 construction program; in accordance with the 1922 Washington Naval Treaty four were scrapped incomplete and two converted during construction into the Lexington-class aircraft carriers.

Later, in accordance with the 1930 London Naval Treaty, they were reclassified as "Heavy Cruisers" (CA) in 1931 due to their 8-inch (203 mm) guns.

It imposed limits that resulted in the smaller displacement Atlanta class with a 5-inch (127 mm) dual purpose rapid fire main gun battery, the first such ship in the Navy.

Early in the war nine Cleveland hulls would be diverted for conversion into Independence class light aircraft carriers (CVLs).

The major noticeable difference would be that the Fargo and the Oregon City classes would have their engine exhausts trunked into a single funnel to aid anti-aircraft fire.

[22] Late in the war the Baltimore-class would also serve as the basis of the two Saipan class light aircraft carriers (CVLs).

Long Beach class The motivation for the large cruiser concept came from the deployment of Germany's so-called pocket battleships in the early 1930s, and from concerns that Japan would follow with similar ships.

She was designed on a light cruiser hull so she could carry a greater variety of detection gear than a destroyer.

[27] On 18 March 1949, the surviving light cruisers of the Atlanta and Juneau classes were redesignated as antiaircraft cruisers (CLAA) without changing their hull numbers; San Diego, San Juan, and Flint were redesignated even though they had been decommissioned and were in reserve.

Atlanta class Atlanta class (Oakland subclass) Juneau class By the end of World War II the Navy had gained favorable experience with dedicated amphibious command ships, and desired similar but faster ships to accompany aircraft carriers for fleet command, which would also relieve overcrowded fleet command facilities on other ships.

These ships would be absorbed into the National Emergency Command Post Afloat mission, and then retired when that role was cancelled.