STORM2K

If the Diego Garcia is only approximately 4 feet above sea level, and the tsunami caused 6 foot surges, then why was it not wiped out?

Think about it -

Diego Garcia (the "armpit" of the Indian Ocean - per service personnel) - the original elevation "was" the 4' msl.

However, in the many years that the island(s) were
occupied by allied forces - including the USA, considerable
contruction has occurred, with hardened piers, buildings,
major installations, and built-up sea protections, etc.

Now, 10 + foot sea wave(s) would do little damage to
the island(s).

Diego Garcia is a major strategic/tactical base for the
military forces of several nations, including the USA.

One must also consider the depth and slope of the Indian Ocean north and east of Diego Garcia. Just as with a hurricane produced storm surge, if the slope offshore is steep and very deep, the surge or tsunami height will be much less than if it encounters a shallow slope in shallow waters.

PW

Diego Garcia is protected by the tsunami by a coral reef that surrounds the island.
I read this in a associated press article.