Mr Walker found the deaths had been "entirely avoidable" and blamed a series of "glaring failures" that led the plane to be labelled as a hostile missile.

BBC: NEWS | UK | UK Politics | US 'must send inquest witnesses'

That potentially devastating prospect may serve as a further disincentive to a hostile power's launching the missile in the first place.

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Aegis began as a sea-based defense against hostile aircraft, but over three decades has evolved to become the most versatile missile-defense system in the world, due in no small part to the fact that destroyers and cruisers hosting the system can get wherever they need to be quickly.

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