The Balance of Power appears to be shifting.
I have been noticing for a while that my new male cat, Tien, has ceased to cower before Isabeau when she growls and bats him in the head with her (declawed) front paws. And it has been a number of weeks since I last saw him hiding under the bed. In fact, Tien has recently been asserting himself by getting in Isabeau's face (literally, facing her nose to nose). However, until tonight, I have never seen him be the aggressor. For the first time, I saw him actually charge Isabeau (who had been growling at him and charging him because it was near feeding time), raise his paw and bat her. She was leaning waaaay over, ready to roll over completely and use her hind claws. When Tien charged, she let out a mighty loud shriek, at which point I intervened for the sake of my (and my neighbors') eardrums, and because it looked like the disagreement might turn serious. I had a talk with both of them to calm them down. It will be interesting to see what develops next, now that Tien seems to have had enough of being a pell for Isabeau.