Ask HN: Does immigration to the US hurt developing countries?

I ask this because my friend from Pakistan, who has studied in the United States, was telling me that she constantly has to struggle with the decision between living in Pakistan or moving to the US or Canada as her sister had done.

In her words, "who will help Pakistan develop if the educated leave at the first opportunity?"

We encourage immigration to the United States, but I believe in the grand scheme of things we are hurting other nations by draining them of their best talent.

As an American I obviously benefit from this arrangement, but I can't help but feel guilty about it.

Would increased restrictions on immigration into the US actually help other countries? Are people who want increased immigration into the US inadvertently hurting the chances of developing nations to fully develop?