He who acts under an emotional impulse also acts. What distinguishes an emotional action from other actions is the valuation of input and output. Emotions disarrange valuations. Inflamed with passion, man sees the goal as more desirable and the price he has to pay for it as less burdensome than he would in cool deliberation.
There is no connection between imperialism and democracy. I mean when we ran an Empire which we did when I was born, there was no democracy anywhere.