Be a global citizen
If we are selfish in our personal lives, we create problems for all around us, but when nations are selfish, the world suffers.
As citizens of a country, we can choose to be so-called patriotic and proclaim that ours is the best or greatest country on earth or whatever, but what are we really doing when we say that? In effect, we are raising our country up to be more important than others, but also perhaps even than the earth itself. A country is just a pyramid belief scheme that leaders in other nations recognise, but if it gets invaded, its status as a nation can be eradicated, but not so the earth. It exists no matter how we treat it, even if we kill ourselves by letting it overheat and it cooks us all.
Regardless of which country we live in, we are all dependent upon the earth providing us with a climate that allows us to live, so we owe it to ourselves to look after it as best we can. Unfortunately there are many who would rather gather wealth than look after the planet, or anyone else for that matter. To that end, they push that our country is most important and that its interests should be our priority, but that hides that they are the ones really benefitting from our national selfishness.
To maintain a national hegemony, they will shift blame from them to other nations or other peoples, or even sections of their own societies that they can claim are not helping the country in some way, even working against it. By framing their selfishness in national terms, they obscure their own complicity in sabotaging the wealth of the nation. By allowing ourselves to be subverted by such rhetoric and propaganda, we allow the earth to be overexploited, which has led to our climate crisis.
Treating our nation's people as more important than others promotes worse outcomes for those others, as it results in each of us consuming far more resources than them, while denying them the opportunity to improve their lives, just because satiating our selfishness relies upon their exploitation. Rich nations built their wealth by conquering other peoples, then, to further reduce their capacity to improve their lives, by economic exploitation and sabotaging their fledgling democracies by corruption, or plain overthrowing their governments and installing dictators.
The only way to stop such exploitation is to stop believing in rampant selfishness, whether at a personal, group or national level. If we instead see ourselves as world citizens, we can then work to give the planet and all people on it a chance to share in equitable distributions of wealth and prosperity, though not in the proportions that has allowed a minority to bring the earth to the edge of exterminating us all. There is enough for all, but only if we take what we need to learn and understand about the planet and ourselves, and not our self-aggrandisement.