The response has two parts.
1. The first is to point out that the logical consequence of this approach is for no one to act, even major emitters, and so we would collectively march to disaster – a classic “tragedy of the commons” outcome.
But this elicits a follow-up argument that there is still no point acting until everyone acts simultaneously since free-riders will undermine one’s effort. This triggers the second part of the response.
2. It is true that the ideal is for everyone to act simultaneously. This would be wonderful. But, realistically, this is extremely unlikely since humanity lacks effective global governance, as 20 years of failed United Nations climate negotiations have shown. So, again, the logical outcome of the demand for simultaneous action is to collectively march to disaster.
An effective way to make this point is to ask what we should do in our jurisdiction in the face of this world reality – eventually arguing that the answer (below) is trivial, obvious to any child.
If (1) we do not want disaster, and (2) we know that humanity will not initially act in unison, then the only logical response is for individual jurisdictions to reduce their carbon pollution while simultaneously trying to get other jurisdictions to also act. One cannot possibly convince others to act if one is not acting oneself. And, even if one is acting, pressure of some kind is likely required to get others to act. This is likely to be restrictions on trade that help domestic industries compete with industries located in jurisdictions without effective climate policies.
Thus, the most likely path to success looks like this. The jurisdictions that are most motivated must act first. They may be motivated because they have an enlightened understanding of the path to success (northern Europe perhaps), or effective environmental governance institutions (California perhaps), or a special incentive because of higher global warming impacts (islands like the UK and Japan, climate-vulnerable regions like Australia). Initial efforts at trade restrictions will be difficult. But once the number of jurisdictions has passed a critical threshold, the difficulty will diminish rapidly as trade pressures mount on non-acting jurisdictions.
In the March issue of the Canadian magazine, The Walrus, I used Canada’s experience in confronting the global threat of Nazi Germany as an example of how to present these logical arguments. Here is an excerpt from that article.
We hear, “Canada contributes only 2 percent to global emissions, so there is no point making an effort until everyone acts at once.”
Yet every year on Remembrance Day, the prime minister extols our critical role in confronting Nazi Germany’s global threat. He fails to mention that we actually contributed less than 2 percent of the Allied effort in World War II; one million Canadians served in our armed forces, compared with over 60 million who fought from the USSR, the US, the British Empire, France, Poland, and other countries. Even though we were only 2 percent of the solution, we have something to be proud of. We punched above our weight by joining France and England in declaring war on Germany in 1939, without knowing if and when the USSR and the US would join the cause. We did not wait for everyone to act simultaneously against a global threat, which is virtually impossible, but instead showed leadership. If we were to show leadership on climate, we would join forces with other leading regions, such as California, Europe, Australia, and Japan, and as this effort snowballed we would use trade measures if necessary to bring other countries along.