Size of the Navy and their scope dictate the size and firepower of ships.
India (by dint of size and fighting power) has a blue water Navy and has destroyers in addition to having frigates. Bangladesh does not (yet) have ambitions of being a blue water Navy being a small developing country and is satisfied being a brown water navy. For brown water Navy like that of Bangladesh, Algeria, Thailand or Pakistan, having some frigates are fine as dictated by their naval war-fighting doctrine. Doctrine dictates the tools to fight a naval war (or readiness of it).
The United States, Russia and (increasingly) China now have destroyers, as does India. Destroyers usually displace around 8000 to 9000 tons and head up fighting battle group formations with frigates and corvettes. Aircraft carriers also form special (expeditionary) battle groups of their own.
Cruisers and Battle cruisers are larger than destroyers (in the range of 12000 tonnes displacement) and only Russia and US have them now (Japan built the Yamato at 45,000 tons in WWII - largest warship at that time). Modern Examples of cruisers and battle cruisers,
1.
Yamato (大和) was the lead ship of the
Yamato class of
Imperial Japanese Navy World War II battleships. She and her sister ship,
Musashi, were the heaviest and most powerfully armed battleships ever constructed,
displacing 72,800 tonnes at full load and armed with nine 46 cm (18.1 in)
45 Caliber Type 94 main guns, which were the largest guns ever mounted on a warship. Neither ship survived the war.
2. The
Iowa-class battleships were a
class of six
fast battleships ordered by the
United States Navy in 1939 and 1940 to escort the
Fast Carrier Task Forces that would operate in the
Pacific Theater of World War II. Four were completed. This class displaced 57,500 long tons (58,400 t) (post 1980s full load).
USS Iowa fires a full broadside of nine 16-inch (406 mm) / 50-caliber and six 5-inch (127 mm) / 38-caliber guns during a target exercise. IOWA was re-equipped with modern day missiles in the GULF war as seen in image below (diagonal and other canisters amidships). Note the huge pressure bowl created in the sea surface.
3. In more modern times (past the 1980s), the
Kirov-class battle-cruiser (
28,000 tons) was launched as a class of
nuclear-powered warship of the
Russian Navy, the largest and heaviest
surface combatant warships (
i.e. not an
aircraft carrier or
amphibious assault ship) in operation in the world. Among modern warships, they are second in size only to large
aircraft carriers, and of similar size to a
World War I era
battleship. The official designation of the ship-type is "heavy nuclear-powered
guided missile cruiser" (Russian: тяжёлый атомный ракетный крейсер). The ships are often referred to as
battle-cruisers by western defense commentators due to their size and general appearance.
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