The Iranian state fields two separate militaries.

The first is its regular army, the Islamic Republic of Iran Army, or Artesh. It does regular military stuff: territorial protection, power projection, etc.

The second is the Islamic Revolutionary Guard Corps, or IRGC. Its mandate is the protection of the “Islamic Revolution” of 1979 and the resulting Islamic republic. It is, in short, the ideologically-oriented component of the Iranian armed forces.

This arrangement is pretty typical in autocratic regimes as a mechanism of ensuring the regular armed forces are kept in check as a potential coup threat. Hitler built the ideological SS in parallel to the regular Wehrmacht; Saddam Hussein built the Republican Guard in parallel to the Iraqi army. Trump has taken initial steps to do something similar with ICE.

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