With further globalization of economic strategies among the industrially advanced nations, fostering and securing "brains" in the scientific and technological fields has become of utmost importance to every country.
It used to take a while before an invention, no matter how valuable, is recognized as having the potential to be converted into practical use. Nowadays such lead time has been extremely shortened. For example, no sooner did professor Shinya Yamanaka of Kyoto University announce the successful creation of an induced pluripotent stem cell than there started keen competition throughout the world for establishing the regenerative medical technology based on iPS.
For any country to prevail in the stiff competition resulting from these rapid changes it is indispensable to secure young, excellent human resources. That is why the United States and other advanced countries have carefully crafted strategies for recruiting promising talent from other countries.