Steyn:

The minute a first-world country has "free" health care, it becomes the provider of choice to anyone who can get there, particularly for any long-term ailments requiring state-of-the-art medications. In 2004, Britain's Health Protection Agency revealed that 44 percent of HIV patients being treated by the National Health Service were not residents of the United Kingdom at all, but from southern Africa. In essence, a huge number of AIDS patients in South Africa, Zimbabwe, Zambia, Malawi, Swaziland, and Lesotho have decided to outsource their health-care needs to British taxpayers. Similar trends will manifest themselves here in nothing flat.

And if people think that's good, and a form of charity we should take on, then the should should simply be honest about that view and defend it, rather than being dishonest and saying it won't happen. (For the record, I think there are many other forms of charity would would save far more lives for far less money, like Malaria protection or helping provide clean water sources.)