When it significantly impacts the daily lives of a majority of people, and not a second earlier.

Educated people around the world already want to do something. Uneducated people outside America already want to do something (because their governments are on board.) It is uneducated Americans -- and their president -- that is going to do us all in.

This means the survival of the planet depends on our ability to communicate with and convince uneducated Americans. That's hard. Al Gore tried long ago with his movie.

Carbon emissions are going up globally, carbon emissions went up in the USA, slightly different political environments won't change the reality that the vast majority of people, societies, and companies have done far less than they need to already. We can't fool ourselves into thinking a democratic presidential win in 2020 will stop this crisis, it simply won't be enough by any rational view of the emissions already out and coming out every day. Even the favorite policy of democrats/progressives, the carbon tax, got voted down in multiple progressive-state reforanda.

In summary, it feels good to point the finger of blame at the current political regime, but the reality is very little is being done anywhere except for pockets of hope like Norway, California, Iceland, Hawaii, which are NOT enough to balance out historical emissions and rising emissions in China, India, etc.

But the resistance to doing something about it is not coming from educated people, at least in the US.

Regarding India and China, their governments are on board and they are making progress: https://qz.com/india/1475736/india-is-now-a-world-leader-in-... https://www.forbes.com/sites/dominicdudley/2019/01/11/china-...

Most uneducated people outside America live worse lives than uneducated people in America, so they have much more important and immediate things to care about than global warming.

Honduras is being impacted. Our reaction in the USA is to block the refugees fleeing famine and drought from reaching us and “invading”. Similarly with Europe and African refugees.

People don’t care.

Tigers disappeared because of humans. Not the natural ebb and flow of the planets rhythms. Less humans = less impact.

>With an estimated 5,000 tigers, the U.S. captive tiger population exceeds the approximately 3,200 tigers in the wild.

While not just Texas that is still insane.

From Wikipedia: "The most comprehensive study of deaths due to tiger attacks estimates that at least 373,000 people died due to tiger attacks between 1800 and 2009, the majority of these attacks occurring in South and Southeast Asia.[1] Over the last five centuries, an estimated 1 million people have been eaten by tigers.[2]"

https://en.wikipedia.org/wiki/Tiger_attack

The concept of a tiger is an important part of human culture, and it would be a pity if nobody could see a real one, but they breed in captivity, so people can see them in zoos. It's easy to romanticize the idea of "wild tigers" when they live far from you, and you're at no risk of one eating you or your livestock. Humans killed most wild tigers for good reason.

Human beings are not supposed to be apex predators but we have taken over that role without embracing the intricacies of the responsibilities involved with it.

To all the downvoters, what is the maximum number of humans eaten by tigers per year you'd be willing to accept in exchange for allowing them to roam free?

Don't try to build such a general argument on such marginal premises. Humans kill far more humans that Tigers ever have. Tigers are simply not a serious threat to us.

All of them.

Certainly there are bad zoos, and I support legislation to enforce high standards of animal welfare, but the only animal I am aware of that is absolutely unsuited to captivity is the killer whale (which IMO might be smart enough to have some philosophical understanding of abstract freedom).