“Mosaic defence” is an Iranian military concept most closely associated with the Islamic Revolutionary Guard Corps (IRGC), particularly under former commander Mohammad Ali Jafari, who led the force from 2007 to 2019.

The idea is to organise the state’s defensive structure into multiple regional and semi-independent layers instead of concentrating power in a single command chain that could be paralysed by a decapitation strike.

Under this model, the IRGC, the Basij, regular army units, missile forces, naval assets and local command structures form parts of a distributed system. If one part is hit, others keep functioning. If senior leaders are killed, the chain does not collapse. If communications are severed, local units still retain the authority and capacity to act.

The doctrine has two central aims: to make Iran’s command system difficult to dismantle by force, and to make the battlefield itself harder to resolve quickly by turning Iran into a layered arena of regular defence, irregular warfare, local mobilisation and long-term attrition.

That is why Iranian military thinking does not treat war primarily as a contest of firepower. It treats it as a test of endurance.