Confusion worse confounded

There are many things about the world and life in general that I don't understand.  Most scientific facts are way over my head; quantum physics, Einstein's Theory of Whatever, how electricity can be used but still flow through the negative side of the plug - all sorts of complicated things like that.  And as for macro- and micro-biology or economics - indeed, anything micro- or macro-.  As far as I'm concerned, the only difference is one letter!

Those things - the things I don't understand - don't bother me in the least.  Although it's not actually the things that don't bother me, it's the fact that I don't understand them.  I don't exactly understand all the why's and wherefore's of the internal combustion engine, but I'm happy enough to drive my car.  There is, however, one thing I don't understand where my lack of understanding irritates the hell out of me.  It's been brought to my attention once again this week by the visit to London of the Chinese Prime Minister or Great Panjamdram or whatever he is.

Our Prime Minister has hailed as a great success and earth-shattering achievement the fact that he has persuaded the Chinese to seek investment opportunities in the United Kingdom.  Like putting up cash for the high-speed rail link between London and Birmingham.  Why is it considered such a "good thing" for other countries to invest in our businesses and industries?  That's what is bugging me.

There was a time - OK, about 150 years ago - when this country was possibly the most powerful in the world, both militarily and economically.  And how did we achieve and maintain our economic superiority?  By investing in other countries!  We paid for railways in South America, we developed mining industries in various parts of the world and so on and so on.  But now we rely on other countries to invest in us.  More than rely on, we actively encourage it.  The high-speed rail link from London to the Channel is owned by the Ontario Teachers' Pension Fund; much of our transport  is owned by the French; airports are owned by the Spanish; our car-making industry is owned by the Indians, the Japanese and the Germans; electricity is supplied by a French company; our chocolate companies are owned by the Swiss and the Americans.  Damn it, even our football clubs are owned by Russians, Americans, and Arabs!

I recall that, as a raw recruit into one of England's banks back in 1960, in the strong room we still held a number of stock certificates in an Argentinian railway company.   British merchants had invested in this business to build railways in a country on the other side of the world.  granted, the Argentinians had the benefit of a modern railway system, but the real beneficiaries, those who reaped the profits, were British merchants.  Could the same thing be happening in reverse?

Can anyone end my confusion by telling me just why it is such a good thing for this once-great country to be holding out the begging bowl in this fashion?