South Korea's and Japan's new helicopter carriers could also one day be useful for moving troops in United Nations peacekeeping operations.

ECONOMIST: Asia's navies

Russia has already ordered two French-built Mistral helicopter carriers, allowing it to rapidly deploy hundreds of troops and dozens of armoured vehicles on foreign soil.

BBC: Russia plans $650bn defence spend up to 2020

Besides new submarines and destroyers, the South Koreans, like the Japanese, are commissioning helicopter-carriers.

ECONOMIST: Asia's navies

Blackhawks have been used by Colombians in the past, not only as troop carriers, but also as helicopter gunships.

ECONOMIST: Colombia