You need time and you especially need time to think. It may not seem like it, but idealism affords you both.
Just to reiterate, in case a previous point got lost, nobody ever dreamed of being less. Nobody ever dreamed of settling for what is unjust. To dream means to aim for something better than just what saves time and skips thinking over or skirts soul-searching.
We came from the depths of dark caves. It was not easy for human beings to get to this point. But the price for being alive always meant that it was never going to be easy to be the right kind of person.
And there is a right kind of person. It is someone who can dream of better things even when faced with a less than ideal situation. It is someone who welcomes taking time to think over solutions to difficult problems. It is someone who can wield the practicality embedded in idealism.