I found this quote from David Horowitz at frontpagemag.com. It was taken from Horowitz's book "How to Beat the Democrats."
Their [progressives'] cyncism flows from the very perception they have of right and wrong. They do it for noble ends. They do it for the progressive faith. They do it because they see themselves as gods, as having the power — through correct politics — to redeem the world. It is that terrifyingly exalted ambition that fuels their spiritual arrogance and justifies their means.
And that is why they hate conservatives. They hate you because you are killers of their dream. You are defenders of a Constitution that thwarts their cause. They hate you because your “reactionary” commitment to individual rights, to a single standard and to a neutral and limited state obstructs their progressive designs. They hate you because you are believers in property and its rights as the cornerstones of prosperity and human freedom; because you do not see the market economy as a mere instrument for acquiring personal wealth and stocking political war chests, but as both means and end.
Conservatives who think progressives are misinformed idealists will always be blind-sided by the sheer malice of the left — by the cynicism of those who pride themselves on their principles; by the viciousness of those who champion sensitivity; by the intolerance of those who call themselves liberal; and by the ruthless disregard for the well-being of the poor on the part of those who preen themselves as their champions.
Conservatives are surprised because they see progressives as merely misguided, when they are, in fact, morally – and ontologically — misdirected. They are the messianists of a false religious faith. Since the redeemed future that justifies their existence and rationalizes their hypocrisy can never be realized, what really motivates progressives is a modern idolatry: their limitless passion for the continuance of Them.