Every State which is sufficiently powerful aims at foreign conquest ; apparent instances to the contrary only arise where a State, from experience, knows itself to be less strong than it seems, or, from inexperience, believes itself to be less strong than it is. The broad rule is that a State conquers what it can, and stops only when it reaches a frontier at which some other State or States can exert a pressure as strong as its own.
Source: Power, 1938.
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