I find much to agree with in Hanson's writings, but in this case I just don't find him convincing...One hypothesis is that smoking causes long term cumulative damage, and you might not see effects in mice or dogs because they die too soon regardless.

So: heads I win, tails you lose? If the studies had found smoking caused cancer in animals, well, that proves it! And if they don't, well, that just means they didn't run long enough so we can ignore them and say we "just don't find them convincing"...

There is also the issue that we have a fair idea of the carcinogenic mechanism now, so if you think smoking does not cause harm, there also needs to be a story how that mechanism is foiled in humans.

You don't think there were plenty of 'fair ideas' of mechanisms floating around in the thousands of animal studies and interventions covered in my animal studies link? Any researcher worth his degree can come up with a plausible ex post explanation.