It's not just that trade allows us to partake of the entire cornucopia of delights that the wider world can provide: it's that the poor get rich when we so partake. Have a look at this chart of Chinese manufacturing wages.
Now I agree, a $1 an hour, as much as $2.50 in a city, these aren't the sort of wages that are going to trigger a mass transfer of population from London to Beijing. We actually make it illegal for you to sell your own labour for less than around $9 an hour.
But look at the rise in those wages! More than doubling* in only six short years! This is stupendous growth, virtually unheard of anytime, anywhere.
There are those who say that we shouldn't in fact be buying these things. Partly because doing so deprives some of our own (it doesn't), partly because those wages being paid are exploitative in some manner (they're not). But, for a moment, just pretend that these things are true. It would still be morally righteous for us to go on buying Chinese goods, if that's what we desire to do. For look at the effects of our doing so: the poor are getting rich.
And isn't that what we all want to happen, the poor to get rich?
* Yes, it is nominal wages but even so it's an astonishing rise given China's inflation rate.