No it isn't. It's required by law to pay taxes just as it is required to pay your employees and not kill them at the end of the day.
So you're saying it's not strictly a negative externality. The moral content or intent of a policy is completely irrelevant to whether it creates an externality or not.
Just because it would be cheaper if this law didn't exist doesn't make it an externality.
Of course not. It's incurred without choice by the employer, that's what makes it an externality.
I don't think you will ever understand what an externality is. There isn't much more I can do here. I understand that you will never want to lower CO2 emissions if you don't get what an externality is.
Funny, doesn't look like that from my end. While I grant someone seems to have a problem understanding what an externality is, I find it more interesting that merely characterizing this massive synergy of fossil fuels, energy, and transportation with the entirety of an economy, as not an externality is sufficient to dismiss it.
This strikes me as comparable to the argument from authority fallacy you presented earlier, created by presenting "credible, peer-reviewed", but highly biased predictions as if they were the best possible guesses out there.
Sure, if we ignore contrary evidence, like what I've remarked on (such as ignoring the positive externalities of fossil fuel use, proper time value of money, or the oter systematic biases contributing to portraying radical carbon dioxide emission reduction as something with low costs and large benefits) then sure, we can reach agreement on this. It's just not worth my effort to do so. Nor would it be moral.