The United States has a number of well-known research and intelligence gathering institutions and organizations who at any given time kept those with the ‘need to know’ aware of what is going on in the world both outside the continental United States as well as within. We as citizens of this country are not kept as much informed, despite access to online news sites, television channels dedicated to the news, and even short wave radio connections overseas, as we would prefer to think we are. There is a probability that our government ‘in the know’ people were aware of the upcoming revolts that were brewing. Sadly, we cannot know everything. So there were obviously going to be some factors not foreseen, even by intelligence people.
When a nation has a robust foreign service. When the important intelligence positions are staffed with capable and dedicated officers then we know about what is going on in the world and are better able to respond. We should have known. Shame on the State Department, shame on the ambassadors of these countries. Shame on us all.
The Arab Spring could not have been anticipated. It started with one man's death in Tunisia and spread from there. Previously, there were protests in Iran in June 2009 against the re-election of Mahmoud Ahmadinejad. Although tyrants are overthrown eventually, not a soul could have anticipated how revolts would have spread through North Africa and the Middle East in so little time.
I do not believe it is reasonable to assume that the US should have foreseen the Arab Revolts. The United States has no special power that gives it the ability to see the future and no one should expect it to have that ability. The Arab Revolts happened due to many factors, not something one could forecast ahead of time.