It didn't stop? So Thailand, Burma, India, Nepal, Pakistan and so on all immediately went Communist?
A better example I would use would be dealing with a gangrenous limb. Or a sick cow living in a pen with a herd. But domino works too. But its political concept based on a metaphor, so yeah, its not going to be 100% accurate in describing what actually happened.
"I'm going beat the crap out of you!"
"No you wont, because I just went to the bathroom and successfully evacuated myself!"
"I'm going to knock your block off!"
"No you wont, because I don't have a block on my body!"