The evidence is available to everyone. I'm not going to summarize climate change for you. And for two specific reasons:
First, I don't know what group you're in. Group 1, you want me to demonstrate that the earth is warming? No thanks. Group 2, you want me to provide evidence that global warming is anthropogenic? Again, ....read. There are countless books, peer-reviewed scientific journals, articles, videos, periodicals, etc. that are available to everyone. It's 2020. Google it. Type "Climate Change" in to Amazon and order a few books. Start with this one: https://www.amazon.com/gp/product/1612198023?pf_rd_r=9M7GK2BS4CGF80WE05JP&pf_rd_p=edaba0ee-c2fe-4124-9f5d-b31d6b1bfbee. Also search for references and literature within the DoD. There's tons available. The Navy, Marines, and the Joint Staff are full up on this while the AF in particular is lagging.
Some might say that me not laying out the evidence is a cop-out. That's fine. Teach me how algebra works. Teach me meteorology. Or chemistry. On an internet forum. Present evidence, or else it's just "religion."
If a flat-earther asks you to present evidence that the earth is in-fact spherical, where do you even begin?
Second, I don't have any confidence that it would matter. You've made up your mind, ...and you know it. You think the models are based on 'assumption.' Specifically, you don't think ice core samples are valid, and therefore the main way we derive data dating back to 800,000 yrs is all invalid. That's fine. But you can see why if that's your starting place, it would be a waste of my time to engage and try to prove otherwise.
What I will do is to again reiterate that time will serve as the vindicator. (*Although I don't know how old you are. If you're in your 60's or 70's, you'll go to your grave never knowing you were wrong. If you're under 40, and live to US expectancy, my point stands.)
See, in you're mind, AGW is wrong, faulty, etc. And under that logic, surely, there will be a time in the not-so-distant future where mankind will discover that all the science and evidence was mistaken. "Oopps! I guess it's just cyclical and 'the earth is gonna earth.'" <sigh> Or better yet, it will be reveled that it was a lie perpetuated by nefarious actors in order to tax people. Well, again, I've got news for you. It's neither. And I encourage you, every 5-10 years, to ask if your ideas on AGW have been shown to be true, or whether AGW is still at the forefront of our discussions on energy, national security, food/water scarcity, migration, etc. Spoiler alert......it's real.
1) I never said we were capable of the "impossible." As far as claiming to be a superpower with global influence, I don't think it's a claim, I think that's a fact, no? As for how long will it last? No idea. .....A very short time if we decide "fvck it," and give up.
2) Don't know. I assume significant changes to the US electrical power grid would be gradual. Phased in? With redundancies and back-ups? To mitigate risk? I'm truly not sure what you're getting at.
3) We don't. We can cede the leadership role. And if the current course continues, we will, in our lifetime. To China. I admit I was raised with a post-war American mindset......I harbor ideas about American exceptionalism and the idea that America "is not just one more indistinguishable entity on the world stage, but that the United States has been essential to the preservation and progress of freedom" and that we have a special role to play in that regard.
Increasingly, we hear themes of isolationism these days. I get it. People are tired of endless wars and entanglement abroad. Heavy lies the crown. We can take the crown off, stretch our necks and enjoy the temporary relief, but I'm not so sure we'll like how it feels when another country picks it up and dons it.
4) It won't be the end of life or humanity. Granted, some book titles, news headlines, and politicians speak with that level of sensationalism to grab attention. But few scientists think climate change will 'end humanity.'
Also, very few people talk about 'reversing' climate change. The discussion centers around slowing and/or mitigating. But what will it look like? I don't know. Take for example India. The Ganges river is glacial fed, and the glaciers in the Himalayas are melting at an unprecedented rate, giving the 500 million people in the basin below a false impression of the health of the river. Meanwhile, all indications are that it's going to be monsoon-fed only by the turn of the century. And they're already depleting the underground aquifers. Where will those 500 million people go when there's no water? People don't just sit around and wait to die of dehydration. There will be mass migration across ethnic, tribal, religious, and state lines. ....I'm betting there will be some fighting involved. It won't be the end of humanity, but it'll be a mess. Similarly, what happens when the Colorado river dries up? Or when huge portions of Miami are under water? It won't be the end of humanity. It'll just suck. For some more than others.