Should we push the reset button on economic and political theories of the era?

Should we push the reset button on economic thinking & theories. Have most of them become irrelevant in our era? Back to basics as foundation?

Let me start off with this syllogism:

My parents taught me to sell only what I own and to only buy something when I have the money to pay for it. Were they wrong?

Someone suggested that my parents were wise. But does that mean that they were they right? Or wrong? Did they raise me for success or failure in the real world, based on that mentality (culture)? In other words, was/is that mentality a way to succeed in the modern world? Or a barrier? Just discussing.

Someone else suggested that if everyone did the same the economy would implode. Did he mean that credit based capitalism would implode? Assuming so. what does that then imply about its fundamentals? Sound or shaky?

Moving on:

Capitalism: Storing value is one thing, but Is it "OK" to make money (profit) from lending/investing money?

Moving on:

Many (eg in Britain) talk re "Sovereignty" vis-a-vis EU.

But:

How sovereign is a country that has financial obligations to foreign countries or nationals?

How sovereign is a country that takes instructions from foreign private organisations, media or "houses"?

How sovereign is a country that relies on foreign investment or foreign consumers or has a trade deficit?

Can't/shouldn't a sovereign have the freedom/power to walk away from any foreign or international legal (eg EU and its set of laws in the form of transposed directives or regulations) or financial (eg debt) obligation to another sovereign or a non-sovereign entity or even a private entity?

What about the sovereignty of the human race as a whole vis-a-vis global warming, radiation pollution risks, HIV/AIDS, cancer, famine, etc?

Sovereignty of a) nations, b) states (a state is not necessarily/usually a nation) or c) the human race? d) __________?

Moving on:

If the world is indeed global nowadays, then why do we still have ranking of countries in many areas/things? Why is there no label "Made on Earth"? Is it a global world or a global championship between countries?

How can one be a "citizen of the world" when the world is not a single Polity or state (in the Platonic sense)?

Is there a European union or a European championship between 27 countries with the EU institutions as the governing body & referee?

Just thinking, philosophising, etc. Because and therefore I am.
In 2011, is it "I think therefore I am" or "I am therefore I think"? Or both? Or neither (seems the case)?