If Donald Trump seriously wants to surround himself with "the best people," by which I think he means people generally aligned with his viewpoint but who are serious thinkers and learned in their fields, he might start with Victor Davis Hanson.  Hanson has this article in the City Journal.

Once again, as in the case of the Tsarnaevs and San Bernardino murderers, the shooter and his associations were on federal authorities' radar--and again to no avail. Apparently, dozens of Americans must be massacred every so often so that the rest of us can avoid the politically incorrect charge of being "Islamophobic." At some point, intelligence authorities will have to take seriously American-born Muslims who consume ISIS propaganda and espouse radical Islamic hatred.

Still more monotonous themes: as in the case of Major Hasan (the Fort Hood jihadist), the Tsarnaev clan (Boston Marathon), and Syed Rizwan Farook (San Bernardino), there is something deeply wrong with American immigration policy and the attitude of us, the lax host, to newcomers. In too many deadly cases, a generation of Muslims goes to great lengths to reach the United States only to raise an American-born or naturalized ungracious and unappreciative generation that apparently grows to hate the bounty and freedom of America to such a degree as to blow up, shoot, and maim innocent Americans. Immigration to the U.S., and citizenship itself, should be seen, again, as a privilege, not a right--and assimilation and integration, not multicultural separatism and ethnic and religious chauvinism, should be the goal of the host. We need not single out Muslims in terms of restricting immigration, but we should take a six-month timeout on all would-be immigrants from countries in the Middle East deemed war zones--Afghanistan, Iraq, Iran, Lebanon, Libya, Palestine, Pakistan, Syria, and Yemen--not only for our own immediate security but also to send a general message that entrance into the U.S. is a rare and prized opportunity, not simply a cheap and pro forma entitlement.