Tightened immigration controls introduced under the 'war on terror' are restricting the flow of foreign researchers into the United States. Many scientists have had to wait months to gain entry to carry out their research, while others have had their visa requests refused outright.

In this article, Nature asks whether the United States' draconian response to the terrorist threat will cause a fundamental shift in the international movement of researchers — and perhaps even alter the global balance of scientific power.

Many top class scientists are already being put off from applying for research positions in the United States, preferring instead to opt for countries such as the United Kingdom and Australia, which do not have such tight restrictions. According to many US researchers and university officials, the US scientific enterprise may suffer as a result.
 

Link to full article in Nature

Reference: Nature 427, 190 (2004)

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