To me politics is all about Power.
That power can be derived from four possible sources:
1.Tact
2.Money
3.Goodwill
4.Ancestry (Of course, this is no longer a source of political power in most civilized countries)
From there, politics is not only about control, but conflict and trade, those two great sources of money, which you can then use to continue to fuel your political career.
However, conflict is best ignored when you aren't provoked to attack. If another country hasn't done you or one of your allies any harm, or if it isn't infringing upon the rights of a smaller nation, you leave it alone.
So then you can lose and gain money through trade, and it all works out.
Overall, politics doesn't have one particular definition, but I'd say that politics is all about different systems and the way they work, about gaining and having the power to test your ethics as a leader and to put your personal beliefs into practice.