Like earthquakes:  they were almost total mysteries before the advent of the plate tectonic theory in geology in the 1970s.  Now we understand more about crustal movements and subduction zones and the resulting earthquakes.  Earthquakes can't be predicted with precision, no, but seismologists can make predictions like "there's an x percent chance of a earthquake of such-and-such magnitude somewhere on this fault line in the next y years."  What they're measuring is the movement of crustal plates, the consquent amount of energy that will eventually be discharged in movement, the known or estimated plasticity of the relevant rock strata, etc.  So:  predictable, yes and no.  

I guess a lot depends on the level of confidence that holders of debt have--and they tend to react like a flighty herd of herbivores sometimes, ready to run for other parts when they sniff the odor of debt repudiation on the breeze.

We measure "consumer confidence."  Why not measure "creditor confidence"?  Just to offer another project that this paradigm implies.

Industrial society is not sustainable. Unsustainable systems change--or disappear.