How can I bring my girlfriend to the US?

To get a visitor's visa, she needs to apply on her own; you cannot petition for her. She would need to apply and present proof that she is not going to immigrate to the US but that she has sufficient ties to her home country ensuring her return after the brief visit to the US.

This is unlikely. A fiancee petition is more probable.

She can apply on her own for a tourist visa.

Thank you for your service to the country. The answer to your question depends on the country of which your girlfriend is a citizen. Most foreign nationals require a visa to come to the US, even for a visit. Some citizens of some countries do not require a visa to come to the US. If the only question that you have is an application to obtain a tourist visa for your girlfriend, a few clicks on the Internet should get the answer. Most of the time, we do not get involved with tourist visas because they are generally all completed thru the US consular abroad and do not require any involvement of the Department of Homeland Security here in the US. If you are looking to find information on how to obtain permission for your girlfriend to come to the US as a fiance or as your spouse, the military will often have assistance available to you to provide guidance. Alternatively, you can always consult with a local immigration attorney for further guidance. Good luck and thanks again for your service.

She can apply for a visitor visa at the nearest US consulate to her home. Please locate the nearest consulate for more information on how to apply at the following link: http://www.usembassy.gov/ .