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Aegis

Current homeland missile defense architecture. (UEWR = upgraded early warning radar.)

US ballistic missile defenses, 2019

By Matt Korda, Hans M. Kristensen | Nuclear Notebook, Nuclear Weapons

Decoys as simple as balloons can often fool current missile defense systems.

Limitations on ballistic missile defense—past and possibly future

By George Lewis, Frank von Hippel | Analysis, Nuclear Risk, Nuclear Weapons

The Russian S-400 anti-aircraft system, pictured in 2017.. Source: Соколрус, via Wikimedia

The vicissitudes of Russian missile defense

By Alexey Arbatov | Nuclear Risk, Nuclear Weapons