Because he hasn’t already done enough to become a parody of himself, John McCain favors  U.S. military action against Boko Haram:
The United States should send in special forces to rescue the hundreds of girls kidnapped by Boko Haram—whether the Nigerian government gives permission or not [bold mine-DL], according to Sen. John McCain.
This would be a questionable thing to do even if Nigeria’s government requested direct U.S. involvement in a rescue attempt, but to be willing to send U.S. forces into another country without permission from a mostly cooperative government is unduly reckless even by McCain’s low standards. It takes a great deal for granted to assume that the mission would be successful with minimal loss of life for the captives and U.S. forces. Obviously nothing would be gained from a botched or failed raid, especially if it resulted in the deaths of many of the innocents held captive. Even a successful raid would carry substantial risks, and those risks would be even greater if this were done without the Nigerian government’s cooperation. It will come as news to McCain, but most governments around the world would not be pleased to be shown up by a foreign power on their own soil without their permission. Whether the mission was a success or not, sending U.S. forces where they are not invited would have the potential to create significant resentment.
Beyond that, making a rescue attempt could trigger new attacks resulting in more civilian deaths, and it could put U.S. firms and citizens at greater risk from reprisals in the future. Even a successful rescue could complicate the government’s ability to negotiate a settlement, and could perversely prolong the conflict. The U.S. can provide Nigeria with assistance in this matter up to a point, but resolving this problem is primarily their government’s responsibility and one that the U.S. shouldn’t be seeking to assume for itself. The U.S. military doesn’t exist either to support or police other countries’ insurgencies, and we should accordingly be very wary of any proposal to use any part of it in that way.