Who needs the French Revolution?

This is in response to JED's post and DLemma's comment on the same post:

The French Revolution certainly spread the ideas of liberty, equality, and fraternity across Europe, and it expedited the growth and development of the 19th-century ideologies supporting or reacting to those ideas. However, I think the right conditions for conservatism, liberalism, socialism, and nationalism were already in place in Europe before the French Revolution. In other words - you could consider this type of counterfactual - the French Revolution was not necessary for the creation of these ideologies to occur. The Enlightenment ideas had already been discussed throughout Europe for a century. The Industrial Revolution, and the social disparities that came along with it, had already begun in Britain before the French Revolution. If there were no French Revolution, the main difference between this hypothetical situation and the real subsequent history of Europe would be that the Conservative movement would have been considerably weaker.