Thank you for your amazing reply @invest.country!

Eventually, all these supranational bodies then can coalesce and form a global supranational body with a Global Parliament and Global Commission

Interesting conception, but do you think that as a humanity we will be able to achieve that much of unity? EU works, but it still faces a lot of serious problems. The results of current elections show that there are a lot people wanting decrease the level of cooperation between European countries. And we need to notice that EU consists of countries from the same cultural field, with the same traditions and history. I can't imagine my government cooperating with Arabic government (unfortunately).