Economic power is the power of production; Political power is the power of force

What is power?
Power is the ability to act.

What is economic power?
The power wielded by a businessmen is the power to create wealth through production, and trade. In regards to trade in a free market, a businessmen can only entice you to do his bidding, by offering you something that you judge to be of equal or greater value in return as judged of your own free-will. His power is the power of persuasion: the power to appeal to one's mind. Such power is derived by creating value--such as when Bill Gates (Microsoft) creates better products at lower prices. The businessman's spiritual tool is the mind--and its material counterpart--is the dollar.

What is political power?
The power of a bureaucrat of a statist society is the power of fear -- the power to initiate force. He can force you to do his bidding by legally threatening your life and freedom. Such power is derived by destroying, or threatening to destroy values -- such as when your local IRS man confiscates your home for not paying your taxes, or the DOJ threatens you with a jail sentence for being too successful.

What is the difference between economic power and political power?
What is the difference? The difference between political and economic power is the difference between plunder and production, between punishment and reward, between destruction and trade. Plunder, punishment, and destruction belonging to the political realm; production, reward, and trade belonging to the economic realm.

The symbol of the businessmen is a positive -- the dollar -- given to you voluntarily by trade. The symbol of a bureaucrat is a negative -- a gun -- pointed at you. The man who prefers the gun to the dollar, is the man who thinks he will be controlling the gun. The joke is on him -- the results are upon all of us.

How do these forms of power operate under capitalism?
Laissez faire recognizes that political power (destruction) should only be used to fight destruction, i.e., force should only be used to retaliate and defend against those who initiate force -- whether they be a gang of street thugs, or a whole nation bent at war. 

Observe that a man gains nothing from killing an attacker, he is no better off then before he was attacked -- he has only prevented a greater loss (his death) by putting an end to the attacker. Only the mind creates, force destroys. When force is directed towards destroying force, its use is entirely proper, since it protects those who create.