The main idea of the article is to come up with a simple way to compare how much countries are doing to fight climate change. The researchers suggest using a metric called the carbon price equivalent. This metric can show how effective different countries' actions are at reducing emissions. By looking at how much carbon each country would need to pay for their emissions, we can see who is doing more to help the environment. The researchers also highlight issues like how to convert money between countries, different types of emissions, and the impact of policies on other nations. They argue that the carbon price equivalent is a fair and efficient way to measure countries' efforts in fighting climate change.