Yes, I think NATO is beneficial, because military actions have more credibility when several nations are behind them. It is a good way to send a message to an offending country to involve a number of nations in a military action. It also cuts down on the United States acting as the world's policeman.
NATO is not beneficial to average people. To corporations and rich people's bottom lines it is a great thing. But because of this many Americans are losing their economic advantage. They can not compete with the Mexican government so they will have to find other jobs. Some can not compete as well as others.