According to the dictionary of idioms, the phrase “rattle the cage” means:

to make someone angry on purpose I rattled his cage by telling him I hated his art.
Etymology: based on the idea of rattling (making a noise by repeatedly hitting) the cage to annoy the animal inside it.

The Missoula Independent’s George Ochenski ends each “column” thusly:

Helena’s George Ochenski rattles the cage of the political establishment as a political analyst for the Independent.

The problem is, the only cage Ochenski seems to be rattling these days is the one he’s locked himself in by refusing to veer from the same tired formulaic rut.

Here’s how the formula goes.  Like a Mad Lib, a few words change here and there, but the structure doesn’t vary:

1-There is some kind of environmental issue being decided, it might even be interesting.

2-All the Democrats in Montana are pure evil, especially those that are the most popular, those at the top. Because I say so that’s why, and I’ve been around for like hundreds of years.

3-Everyone should do what I say, and not listen to anyone else, except those that I agree with.

I’ve read this formula time, and time…and time again, and it’s beyond stale.   It’s just a guy getting himself worked up by rattling the cage he built for himself, from the inside.