Anarchy’s cohesion-generating claim rests on both empirical and theoretical support

Evidence

The claim that anarchy engenders cohesion is well sustained empirically, but it can also be sustained by theoretical considerations. There is a powerful model which lends support to this contention. The model is constructed with the help of a number of factors actually corresponding to the realities prevailing in an important part of the world. — Diego Gambetta, Trust - Making and Breaking Cooperative…, 1912