Politics is about power. Economics is about sources of power. The fusion of the two is what for? Could the eminent masters of the subject bring it home to me who is for all purposes a layman in economics.
Mohammed, I think that neither politics nor economics set their goals as reaching power, but you are right that some power exists in both cases. Formally politicians cannot accumulate power because they can be replaced after new elections. Economics is not a science of power but of optimal consumption, saving, market organization, etc. But there are powerful players in modern economic world.
I think that Jacques Attali said that the power can be of 3 types: ideological, military and economic. In the time of kings power was more concentrated, and military power has dominated international relations. But the power of king has to be shared with ideological power of church. Globalization made the role of economic (better to say, financial) power more important today.