I think not very far, China is growing and so is Russia, the American giant is coming to a halt with the economic problems. As every empire before it, it has expanded beyond its resources and will face similar problems like every other empire did. I see a bi-polar world coming back again where all the shots are not called by the Americans any-more.
One of the biggest problems that will be faced by most countries is resources. Since our appetite in this consumer based society has reached unparallel proportions, unless ofcourse we go back to being normal days, humans will continue to fight over them bringing much harm to humanity. One must remember how Germany from being the epitome of western civilization that produced the likes of Charles Darwin, Albert Einstein, Karl Marx, Fredrick Engels, Sigmund Freud, Immanuel Kant, Martin Heidegger, Klaus Fuchs, Max planck etc descended into Nazism within a few years of war and social strife.
One must see the parallel in US of A where after the election of Obama Militas exploded all over. According to SPLC from 149 to 1200 which is an increase of 755%.
http://msnbcmedia.msn.com/i/MSNBC/Sections/NEWS/z_Personal/Huus/Year in Hate IR145.pdf
http://articles.nydailynews.com/2012-03-08/news/31137657_1_splc-annual-report-groups
Point being once the economic collapse starts to show its strongest signs there will be a big rebellion, most likely resulting in a big chaos, Possibly breaking up of America as we know it.
Then you have the middle east burning, where a lot of dictators have been removed, armies dismantled in some circumstance which can spell big issues there. Now given Israel which didn't sign the non proliferation treaty is on Iran;s case, and wants America to jump in as they can not single handedly take out that country's plants and sustain a blow back, problems are only beginning.
Syria is another problem where China/Russia Vs. Arab dictators/Nato/America is being played out. China is fast expanding into Africa, including western Asia with defence pacts etc causing Alarm in the white house. I believe soon we will see blood in the streets of Europe as they have been living beyond their means for too long. Greece is the microcosm of what will most likely happen in Europe. The neo Nazi Party is on the rise, suicide all time high, immigrants being attacked and illegal ones deported.
http://www.setimes.com/cocoon/setimes/xhtml/en_GB/features/setimes/articles/2012/09/17/reportage-01
grew from 0.29 to 6.97%. Give it some time, as people begin to lose jobs, homes, businesses they will want to blame someone for their problems. Certainly it cant be how they managed their country, lived beyond their means paying almost no taxes etc, hence it would either be another country, immigrants etc etc.
I do not believe in the Dark Knight scenario where both boats do not press the trigger to blow each other up. I am more into how stuff happened in "the Mist"
http://www.imdb.com/title/tt0884328/
Where people lose their rationality and begin to act insane due to lack of resources and hope. I think it might not be as bad but you never know. Yugoslavia is a good example of how it can go, where people killed, pillaged and raped their own neighbours in the name of nationalism/religion etc.
I think Chris Hedges is more accurate on how things will be falling apart, though i do not share a lot of his other understandings.
Lets hope for the best.