It’s true -you can’t force people to stop smoking as a spouse, but I get the impression you aren’t even encouraging him. “when and if they are ready, you can be there to help them through it,” This sounds like you are waiting for him to make the first move. This is probably a bad idea, being that this might be years from now and at that time he might already have a chronic disease chas’vs. The best thing is to encourage him now to quit. Tell him to go to his doctor, as there are many medications to help people quit smoking.