I didn't ding the post, but I don't agree. The world population going from 1 billion to 7 billion makes an immense difference in practical immigration policy.
Closed borders are like laws that suppress competition, I agree, and I wish open borders existed to all countries. (If they did, i would be one of the first to head for the exit.) But open borders don't exist and it would be a disastrous policy today for the US to open borders to all unilaterally. The ease of travel 100 years ago was negligible for any but the rich. Governments didn't have closed borders in the past because in practical terms there were few able to travel long distances across oceans.
Open borders is a very desirable goal when done in many countries, but it must also be combined with elimination of free gift offers.

Awesome

someone dinged this post. If XenokRoy's statement is anti-objectivist-then stand up and give your argument-coward