A historical system is both systemic and historical. That is to say, it has enduring structures that define it as a system --enduring but not of course eternal. At the same time, the system is evolving second by second such that it is never the same at two successive points in time. That is to say, the system has a history, and it is what it is at any given moment not only because of its enduring structure but because of its particular (indeed unique) historical trajectory.Another way to describe this is to say that a system has cyclical rhythms (resulting from its enduring structures as they pass through their normal fluctuations) and secular trends (vectors which have direction, resulting from the constanty evolution of the structures). Because the modern world-system (like any other historical system) has both cycles and trends --cycles that restore 'equilibrium' and trends that move 'far from equilibrium-- there must come a point when the trends create a situation in which the cyclical rhythms are no longer capable of restoring long-term (relative) equilibrium. When this happens, we may talk of a crisis, a real 'crisis', meaning a turning point so decisive that the system comes to an end and is replaced by one or more alternative successor systems. Such a 'crisis' is not a repeated (cyclical) event. It happens only once in the life of any system, and signals its historical coming to an end. And it is not a quick event but a 'transition', a long period lasting a few generations.
In the terminology of the new science, this is the moment when the system bifurcates; that is, when the fluctuations away from equilibrium are so great that the curve flies off to form one or more new orbits. There is always more than one possibility at this point, and there is no way of determining in advance what the outcome(s) will be... (8)
Periods of global economic expansion and contraction are sometimes referred to as Kondratieff cycles. They typically have lasted 45-60 years, and are sometimes alluded to by historians when they speak of an era of prosperity or one of great depression. We believe that a Kondratieff expansion or A-phase began circa 1945 and reached its peak in 1967/73, whereupon it was folowed by a stagnation or B-phase with is continuing... (9)
Hegemonic cycles are far longer than Kondratieff cycles. It takes a long time for one major power to win a competition with another major power so that it can become fully hegemonic. As soon as it does so, it seeks to use its hegemonic position to prolong its power. Nonetheless, it is in the nature of the capitalist world-economy as a historical system that the very efforts made to prolong the power themselves tend to undermine the base of the power, and thus start the long process of relative decline... (9)
If indeed 1967/73 is also the beginning of a systemic crisis, of the precipitate downturn, what might we expect during the bifurcation --that is, in the middle run? The short answer is disorder, considerable disorder... As in any kind of real historical crisis, there exist real choices that can be made. Those who discern them lucidly and act on them with concerted effort are less likely to lose the outcome they prefer than those who put their faith in the unseen historical hand. (10)