During the Second World War, the difference between a Cruiser and Destroyer was well defined. Destroyers were fast agile ships that relied on torpedoes and small caliber naval guns. Destroyers often displaced only a few thousand tons at their heaviest. Cruisers were larger, with heavier armor and armaments. They relied primarily on mid caliber guns ranging from 6 to 8 inches. It was not uncommon for cruisers to displace well over 10 thousand tons. However, as time went on, the differences between the ships began to diminish. Today, the difference is largely unnoticeable. How did these once completely different classes converge into a singular design that shares everything from size, armament, and even role?
Rise of Missiles
Perhaps the evolution of armaments is the largest culprit. During WW2, aircraft had shown themselves to be superior offensive weapons compared to naval guns. The replacement of battleships with carriers makes this apparent. Following the war, it soon became apparent that missiles would largely replace gun based systems. Missiles allowed even small frigates to possess offensive power rivaling that of battleships. They offered similar firepower with the capability to engage at ranges many times that of even the most advanced battleship guns. Soon guns were regulated to anti-air roles. Even then, they were incapable of engaging smaller, high speed anti-ship missiles. It soon became apparent that the only thing really capable of stopping a missile was another missile. Soon, missiles largely replaced guns in the air defense role as well. Based on these developments, it shouldn’t be surprising that the advancement of missiles corresponds to a decrease in warship size.
Compared to guns, the greatest advantage of missiles was their smaller size. Guns required a lot of deck space. They also needed to be placed in such a way that they could easily be trained and fired. Missiles took up less space and weighed considerably less than gun systems. A smaller footprint allowed missiles to be readily placed in areas of the ship that guns couldn’t.
Naval designers, no longer hindered by gun placement, were now able to better optimize new warships. More space was available for new electronics, better crew quarters, and more efficient propulsion units. Ships could be smaller, but vastly more effective.
Lastly, missiles weren’t just smaller, they were vastly more versatile. A vertical launch cell on a modern Ticonderoga class cruiser can carry anti-surface tomahawk missiles as well as a variety of anti-air missiles. This means that a single vertical launch cell can perform the roles of larger caliber shore bombardment cannons and close range anti-air cannons all in a much smaller footprint.
Simply put the weight and size of weaponry was reduced. As such, the size of the hull needed to carry those weapons could be made smaller.
Cruisers, being armed with intermediate weapons, were given intermediate armor. Heavy cruisers could be armored with as much as 8″ of armor. Destroyers on the other hand, carried enough armor to protect the vitals from aircraft machine guns at best. Both were armored for the environment they were designed to fight in.
The evolution of weaponry completely changed the environment of naval warfare. Weaponry advanced at such a rate that armor could not keep up. Missiles became powerful enough that it was not economical to sufficiently armor a vessel enough to resist them. Following the Second World War, newer ships adopted just enough armor to provide minimal protection at best. Greater emphasis was placed on active defenses rather than passive ones like armor.
With no need for armor, cruisers again lost another defining trait that separated them from destroyers. Today’s cruisers utilize the same armor systems as destroyers. In many cases this is simply a small amount of Kevlar spall armor placed around machinery, magazines, and other important areas.
Important especially given today’s political environment. Crew sizes have become synonymous with high costs. Many forget that the primary reason the battleships were ultimately scrapped were due to the costs of their large crews. Even during the Korean war, when cruisers were still needed, the Navy had to carefully choose which cruisers to reactivate. This is why ships of the Cleveland class were passed over for reactivation despite being in good shape.
The final heavy cruisers used by the US Navy, the Des Moines Class, required a crew of 1800 men. By contrast, the compliment of a Ticonderoga class cruiser or Raleigh Burke class destroyer is 400 and 323 respectively. Future ships are expected to utilize even smaller crews with ships such as the Zumwalt class carrying a crew as small as 142.
Much like battleships, cruisers were subject to numerous cost cutting measures that saw their roles being taken over by smaller, cheaper ships.
The Convergence of Roles
The final death knell for the cruiser was the fact that it no longer had a specific purpose to fulfill. Carriers had become the primary offensive power and their aircraft could perform all the roles once held by cruisers. Besides the odd shore bombardment role, cruisers found themselves regulated to carrier escort. For a short time, their larger size allowed them to carry more defensive firepower compared to destroyers. However, as missiles became more advanced, destroyers found themselves able to do everything cruisers could do at a fraction of the cost.
The end of cruisers is likely imminent. The few ships still classified as cruisers are on their way to being phased out with their roles being taken over by more affordable destroyers. The US Ticonderoga cruisers, while still being upgraded, are existing on borrowed time. A potential cruiser replacement was abandoned for additional destroyers. Russia’s Slava class and the infamous Kirov class cruisers are due to be replaced by the versatile Lider Class destroyers.
Unless advancements in naval technology dictate new designs, the cruiser warship is bound to disappear. Much like the battleship, cruisers as we know them are relics from a prior age of naval combat.
Think the cruiser still has a place in modern naval warfare? Leave a comment below or in the forums section.