Way back in 1902 an English economist, John A. Hobson, provided a simple explanation of the term imperialism, which holds to this day. In simple terms, mass production creates too many products for domestic consumption. This necessitates finding foreign markets, and the capitalists who make the products use the power of their government to secure those markets using military force if necessary. Hobson puts the motivation for new markets this way:
It is open to Imperialists to argue thus: "We must have markets for our growing manufactures, we must have new outlets for the investment of our surplus capital and for the energies of the adventurous surplus of our population: such expansion is a necessity of life to a nation with our great and growing powers of production."
Hobson then puts words to the next logical step: Corporations influencing government's use of the military to secure foreign markets:
After 1870 this manufacturing and trading supremacy was greatly impaired: other nations, especially Germany, the United States, and Belgium, advanced with great rapidity, and while they have not crushed or even stayed the increase of our external trade, their competition made it more and more difficult to dispose of the full surplus of our manufactures at a profit. The encroachments made by these nations upon our old markets, even in our own possessions, made it most urgent that we should take energetic means to secure new markets. These new markets had to lie in hitherto undeveloped countries, chiefly in the tropics, where vast populations lived capable of growing economic needs which our manufacturers and merchants could supply. Our rivals were seizing and annexing territories for similar purposes, and when they had annexed them closed them to our trade. The diplomacy and the arms of Great Britain had to be used in order to compel the owners of the new markets to deal with us: and experience showed that the safest means of securing and developing such markets is by establishing 'protectorates' or by annexation....
What strikes me is that the logic is so simple and it explains the corruption of our government by corporations.