With Thailand sharing a long common border with Laos along the Mekong River, the Thai government was increasingly concerned about the spread of a communist insurgency into Thailand, which already faced a growing insurgency of its own in that part of the country. The Thai government were concerned about the activities of the Communist Party of Thailand It was therefore receptive to the idea of allowing U.S. military personnel to use Thai territory for operations in support of the Lao Government, and later in support of South Vietnam.