@Setanta,
I don't know that there is any reason to believe that we are witnessing the launch of or experiencing the initial stage of a new phase of history.
First of all, I think to consider it a new phase, we would have to believe that the West's interventions are for reasons that haven't been in play in the past.
I'm hard pressed to explain a "new" reason in terms that do not suggest a neo-con philosophy, and I just don't believe the West has gone neo-con.
Secondly, irrespective of motivation, the West is simply not in an economic position to finance such a new phase.
I'm not of the opinion that we are witnessing the inevitable decline of the West, or more specifically, America. I believe the US and the West in general will rebound, but it won't be within the next year or two, and without a thriving economic base, a policy of intervention cannot be funded...without ensuring decline and fall. Civilizations and nations have taken actions that have ensured their fall, but I just don't believe the current dynamics will allow that for the West or America.
Given the current state of the West's economy, it would be a bad idea to adopt a wide scale policy of intervention. Whether or not it's a bad idea, economics excluded, is subject to debate.
In any case, it's not happening.