Let's look at the "when" portion...
While the cycles do happen, they aren't set in stone as far as timing or types of events. Nature does have basic frameworks that it follow, but it is still variable. For a simple example, daisy's do tend to follow the golden ratio and fractal math but each one is still unique and many fall outside of those guidelines. Or... using the traffic on the highways as Randall Carlson mentioned, when the traffic is crowded, an accident is more likely but that doesn't mean one will actually happen. One last example, the Mayan's calendar seemed to indicate some change was going to happen after 2012 came around... but we seemed to miss having any catastrophic none the less.
So the cycles are patterns to be paid serious attention to but at the same time, we must understand there is still a differences in the probability that will always come into play. I don't believe in fate alone, I think our free will can and does have an impact on future events.
If the potential
threat is a meteor or comet... we are at a point in time that our technology could help avert a possible impact. We need to invest and then implement space technology that could help protect ourselves. We should also invest in a backup plan and start moving towards starting colonies on other worlds so if something catastrophic does happen, it can't completely wipe out humans.
