The USA internally, is not a singular country. But a Federation of Sovereign States.

In a federation, the self-governing status of the component states, as well as the division of power between them and the central government, is typically constitutionally entrenched and may not be altered by a unilateral decision of either party, the states or the federal political body. Alternatively, federation is a form of government in which sovereign power is formally divided between a central authority and a number of constituent regions so that each region retains some degree of control over its internal affairs.

Having worked and lived in Germany. Their 'States' are not Sovereign States as with the USA.
Unless their actions involve Interstate Commerce. The Federal Government, there is no American Government, has very limited authority.
Just two of many examples. Think marijuana laws and Sanctuary Cities/States. If the laws are in conflict. Well, too bad.

The USA internally, is not a singular country. But a Federation of Sovereign States.

Not quite.
The USA is a federation/union of partially self-governing states, not sovereign states.
Like Germany and Russia.

In a federation, the self-governing status of the component states, as well as the division of power between them and the central government, is typically constitutionally entrenched and may not be altered by a unilateral decision of either party, the states or the federal political body. Alternatively, federation is a form of government in which sovereign power is formally divided between a central authority and a number of constituent regions so that each region retains some degree of control over its internal affairs.

btw. There are separatist movements in both Texas and California.
Not so successfully ones though :)

Add the separatist movement of New California from California.

•New California declares 'independence' from California in bid to become 51st state•

https://www.usatoday.com/story/news/nation-now/2018/01/16/new-california-declares-independence-california-bid-become-51st-state/1036681001/

Nothing new.

Edit: Having worked and lived in Germany. Their 'States' are not Sovereign States as with the USA.

Unless their actions involve Interstate Commerce. The Federal Government, there is no American Government, has very limited authority.

Just two of many examples. Think marijuana laws and Sanctuary Cities/States. If the laws are in conflict. Well, too bad.

To establish an uniform Rule of Naturalization

The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.

Edit: Having worked and lived in Germany. Their 'States' are not Sovereign States as with the USA.

'marijuana laws'... Per the 10th Amendment, that is supposed to be a State power.

The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people.

The US Constitution is silent on the regulation of various drugs. Therefore it is a State power, just like the regulation of the rest of Medicine is...

marijuana is a plant and one not native to the USA.

...migrating birds have been known to poop marijuana seeds that grow wild...
(It's native if nature does it. :^p)

Sanctuary States and the Sanctuary Cities allowed by the States is another interesting Constitutional issue. Does the Federal Government have the Constitutional authority to force the Internal Sovereign States to notify them of crimes which are not crimes within the States.

If those arrested for State Crimes and would have been quickly released. Does the Federal Government have the Constitutional authority to force the States to increase the time of incarceration. In order for Federal Law Enforcement to arrest this person for non criminal acts within the States?

U.S. adults scored below the international average in all three domains.
Overall, U.S. adults scored slightly below the PIAAC international average in literacy, higher than only Poland,
Ireland, France, Italy, and Spain. In numeracy, the U.S. average was near the bottom of the rankings — only Italy and Spain scored lower than the United States.
In problem solving in technology-rich environments, the U.S. average was only slightly below the international average. However, we shared the lowest ranking with England and Northern Ireland in the United Kingdom, Estonia, Ireland, and Poland.

While a small percentage of adults in the United States perform at the highest levels in all three domains, a much greater percentage perform at the lowest levels.
The percentage of U.S. adults who scored at the highest levels in all three domains was similar to or only somewhat lower than the international average; however, the percentage of U.S. adults who scored at the lowest levels was among the largest in PIAAC. It is this disparity between the small proportion of adults whose skills are among the highest and the much greater proportion of adults whose skills are among the lowest that lowers the U.S. ranking among its peers.

Members of the House on Thursday said they viewed a “shocking” classified memo allegedly detailing abuse of the Foreign Intelligence Surveillance Act (FISA) by senior Justice Department and Federal Bureau of Investigations officials in relation to the investigation of the Trump campaign and called for it to be declassified and available to the public immediately.

‘Worse Than Watergate’: ‘Shocking’ House Intel Memo Allegedly Reveals FISA Abuse by Senior DOJ and FBI Officials -- har...

‘Worse Than Watergate’: ‘Shocking’ House Intel Memo Allegedly Reveals FISA Abuse by Senior DOJ and FBI Officials -- har...

Shrub has consequences.

A former Iranian army chief has accused Western spies of using lizards to “attract atomic waves” and spy on his country’s nuclear program.