People in the U.S.A. forget that "state" means a sovereign nation. Why are the "United States" not actually states? Taxes. Actually thats basically it. After what would be known as U.S.A. was founded, taxes where opt in. but the burgeoning central government was on the hook for all its international debts. and of course no state wanted to pay taxes...or did pay taxes. So they restructured and the "federal" goverment became superior to all states and its power has grown while states rights diminished. So yeah, in some ways wed be alot better if states where thier own sovereignty, and the founding fathers even put a stipulation that any state unhappy with the union can leave, but the last states to do that got the **** beat out of them and it was made illegal (CSA / Civil war).

TLDR; Founding states didn't want to pay taxes, federal government was formed to collect taxes.

the founding fathers even put a stipulation that any state unhappy with the union can leave, but the last states to do that got the **** beat out of them and it was made illegal (CSA / Civil war).

The CSA didn't get their asses kicked for leaving the Union. The CSA got their asses kicked for starting the hot war by attacking Fort Sumter 2 months after seceded. The CSA also doubled-down on keeping slavery legal in their Constitution which burned any bridges for support from Europe which had already abolished slavery long before.

FYI, I didn't downvote you.

and the founding fathers even put a stipulation that any state unhappy with the union can leave

What are you referring to?

There are lots of things that have been accomplished in the USA that would not have been if each of the 50 states operated as separation nations. Besides the obvious of the scientific and medical advancements, the common rules for business across states allows for products and many services to flow mostly uninhibited by each states rules (some exceptions apply).

Having enough resources as a single nation allowed for a common defense which saved the USA a number of times. Apparently this is also one of the reasons some regions of the world fell to colonialism because the various groups that occupied the land were not unified in their goals or defense. It allowed stronger powers to pick of each smaller group separately until the region as a whole was conquered.

I often times wonder if it would be better managed with more of an EU style system where certain standards are core across all states and then leave each country to truly govern themselves.

I like Europe a lot, but they've got some problems directly stemming from the lack of a single nation encompassing all of them. Even to-date there is not a single monetary policy in the EU. This lead to things like the GREXIT crisis. The leadership in Brussels can also get stymied by a single contrarian member halting progress such as Hungary frequently stopping aid to Ukraine.

None of this is to say the USA is perfect or the EU is flawed. There are positives and negatives to both systems. No one has found a perfect system yet.

while no explicit mention of secession, the very act of the revolution and statements such as "...Governments are instituted among Men, deriving their just powers from the consent of the governed,–That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government…" and "...When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another..."have been used to show the idea the founding fathers supported secession.

Only a handful of times has anyone in the U.S.A. seceded, though most of the times it was just to create a new states in the U.S.A. It was officially outlawed after the C.S.A. seceded and not much of any serious attempt has been made since.

while no explicit mention of secession, the very act of the revolution and statements such as “…Governments are instituted among Men, deriving their just powers from the consent of the governed,–That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government…” and "…When in the Course of human events, it becomes necessary for one people to dissolve the political bands which have connected them with another…"have been used to show the idea the founding fathers supported secession.

Neither of those are in the US Constitution. Those are from the Declaration of Independence.