[Llarry]

The second nation to commission an Aegis destroyer was Japan, which took delivery of its first Aegis DDG in 1993. The JMSDF presently has 8 Aegis DDGs in service. They appear to be every bit the equal of their USN counterparts. Considering the hazardous geographic position of Japan, the government also considered establishing an "Aegis ashore" capability to defend against ballistic missiles. I believe they have instead decided to increase their DDG inventory by two to a total of 10. There has also been discussion of dedicated anti-ballistic missile ships that would not have the full range of warship capabilities. We await developments.

The Spanish Navy was the next to put Aegis into service afloat and did so in a smaller package. Their Alvaro de Bazan class missile frigates (FFGs) are smaller than the U.S. and Japanese DDGs but very capable. They have five in service from 2002.

The Royal Australian Navy wanted Aegis and conducted a competition between the U.S. DDG design and the Spanish FFG. The Spaniards won the day (at considerably less cost) and the RAN now has three Hobart class "air warfare destroyers" in service from 2017.

The Royal Norwegian Navy also purchased five Spanish-built Aegis FFGs and put them into service from 2006. Tragically, one Norwegian FFG was involved in a collision and was deemed unsalvageable, leaving four in service.

South Korea's three Sejong the Great class DDGs are similar to but larger than the late-production U.S. DDGs, making them the largest Aegis ships in service. They began entering service in 2008.

Planned/future Aegis combatants:
-- The U.S. Constellation (FFG 62) will have a lighter/less complex version of Aegis.
-- The ROKN plans three additional DDGs for a total of six.
-- The Spanish Navy plans 5 additional FFGs.
-- The Royal Canadian Navy plans to build up to 15 Aegis-equipped combatants to replace existing Halifax class FFHs. If this program is fully funded, it promises to make Canada the Navy with the largest number of Aegis ships other than the USN. Go Canada!
-- There is the prospect of fitting Aegis to new U.S. Coast Guard icebreakers. (I would hope so, but the poor Coast Guard is perennially short on funding.)

It remains to be seen how small a hull can effectively accommodate the Aegis system. Stay tuned.