WAF and friends actaully proposed this sort of thing more then once: Make corporate tax global.

Would they go to more impoverished/desperate nations and build them up with their huge presence, and low wages, despite the cost of essentialy needing to build the infrastructure to operate there?

The reality is that most of the ultra-big publicly traded corporations are horrifically inefficient.

Their business model depends on the central bank "printing" money and then through the banks lending them vast amounts of money at ridiculously low rates. They also depend heavily on various government kick-backs and regulatory concessions.

This is why modern economies are most accurately called "Corporatism" or "Syndicalism". This is a type of socialism that is considered a "third way" between full blown leftist socialism and 19th century capitalism.

Under this model of economic governance you have the combination of these massive national corporations working hand in hand with a massive administrative state.

In the USA we have these massive administrative industries. When they think you shouldn't be allowed to smoke cigarettes, or have incandescent light bulbs, or have shower heads that flow a lot of water... They don't go after you.

Nobody is going to show up at your house to make sure you don't have a 5 gallon toilet smuggled in from Mexico. They are not going to send the FBI in after you if you try to make your own tobacco.

What they do is go after these big corporations and regulate them. And in exchange for their compliance these corporations get a lot of favors done for them. When the government does something to impact their profits the government also does something to offset it... to reward compliance.

And it is through these corporations that they are then able to indirectly regulate you.

Many people operate under the mistaken belief that we need big government to counter the greed of big corporations. Prevent trusts, monopolies, etc.. deal with externalities like the environment/poverty and regulate natural monopolies like power distribution or roads.

The opposite is actually true.

if you ever worked in a heavily regulated industry you'd quickly realize that the government sees it as part of it's job to keep that industry profitable. Think about various monopolies enjoyed by big corporations involved in the telecommunication industry or how the government bailed out banks in 2008, the government bailing out the automobile industry several times, or how the airline industry works. So on and so forth.

So big corporations are not going anywhere if governments somehow figure out how to close all the "tax loopholes". Why? Because no matter what happens they know they can rely on their friends in government to keep them in the black. No matter what.

The actual productive members of society... that is the groups of people that hire the most workers, pay the most wages, and create the most goods and services are small and medium businesses.

That is really who the government goes after in a big way. Because they are not only a dime a dozen... so if a few go bankrupt it is no skin off the government's back. The politicians have no relationship with them, they don't hire lobbyists, they don't have their nephews on the board of directories of some small business.

So they are the source of the most of the wealth and thus have the most to be squeezed out.