What could humanity achieve if the whole world truly worked together?

It seems to me that there would be no limit to what we as humans can do, if the entire world strive for the same goals for the Human Race. Medically, Socially, morally? We would have solved world hunger years ago, world peace years ago, we would be on Mars by now and the Human Race would probably know now limits or boundaries if we all pulled in the same direction. There would not be anything our Human Race could not do.

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3 mo
Well, I give up on any further "what if' questions, since I believe I explained what it would take to achieve this Nirvina place in the universe, and everybody just read over that and put in their 'won't happen" shots.
What could humanity achieve if the whole world truly worked together?
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