The earth has been lots warmer than it is now:
- age of dinosaurs for millions of years, hot, steamy, swampy, odorous, and noisey....
The earth has been lots colder than it is now:
- ice ages, multiple and recurrent (20 plus, and counting) over at least 500 - 750 million years - the most recent ice age ended ~15,000 years ago when the earth went into a global warming cycle again (imagine that)
Yes, man's production of CO2 has speeded up the current global warming cycle - by roughly 100 years ahead of where it would have been without us... To us that 100 years on 'fast forward' is a steaming political issue - in geothermal cycles it is not even a blink of the eye...
Are we in decline (the USA, that is)? Well, that depends on what you measure..
In technology?
Nope, we are Numero Uno, The Big Cahuna, the 800 Pound Gorilla, and the biggest Parrot that ever said, "Polly wants a cracker, N O W!"
We have immigrated many of the best minds of the world for the past 5 generations... We supplied them with the incentives of a capitalist society whereby they reap the rewards of their creative intellects. What an engine of science, industry, and commerce we have created...
In stature per the other nations?
Yup, in decline in how we are perceived... In decline in our ability to influence other nations through the President's Bully Pulpit... In decline in our ability to shape future events... Britain went through the same cycle and lost its empire, so will we eventually... China is the up and comer for the next heavyweight title of World Superpower...
In military power?
Nope, not at the moment.. We are The Super Power militarily... However that title takes lots and lots and lots of money to keep it polished and shiny... Our dollar is in decline currently, and much depends on how that plays out... We saw what happened to the USSR when it ran out of money AND the will to persue power - which are the same thing...
As a country?
I think we are not in decline... The hispanics who flood this country are desperate to achieve the american dream, the good life, La Dolce Vita... In two generations they will be just like us, ugly americans all... (God help em)
We are still the best society in history to live in, we have a responsive political system, the courts have procedures to protect the rights and interests of even the weak, the helpless, and, yes, the criminal among us...
We have the best medical system in the history of man...
(don't get sidetracked into who gets it free and who pays - those are political issues, not science)
World leaders who get ill, and the merely wealthy and well connected, rush to the USA the minute they get a disease... No medical system in the world is better suited to treat cancer, and a host of other complex diseases... Even the pampered citizens of Canada and Britain hot foot it here when they need to bypass the waiting lists and ques of their countries - which is THEIR form of rationing...
Lots to be positive about... Not much will change in our lifetimes... Energy will cost more and it will be harder to achieve the American Dream, but no flat out collapse....
cheers ... denny