International audience In this commentary of Koonin's target paper, we defend an extended view of CRISPR-Cas immunity by arguing that CRISPR-Cas includes, but cannot be reduced to, defence against nonself. CRISPR-Cas systems can target endogenous elements (for example in DNA repair) and tolerate exogenous elements (for example some phages). We conclude that the vocabulary of "defence" and "nonself" might be misleading when describing CRISPR-Cas systems. 2