Exactly, I agree with Iqbals's explanation. A combination of both military and economic power is essential to maintain order in the society and to check rebellious elements. But you see, there must be a sort of balance between military and economic might. Too much military power can lead to downfall, as is evident from the fall of Soviet Union. On the other hand, only economic power cannot make you a 'power' in the world. This is also evident in case of Japan.