With the rapid changes in the Asian-Pacific security environment, China's relations with its neighboring countries entered into a new "run-in period". Owing to the obvious unfitness of both sides at this stage, a series of frictions and conflicts emerged. However, the conflicts have not become a mainstream trend. China faces five challenges to maintain border security and stability under the new situation: fluctuations in the relationships between China and the neighboring countries; increased strategic pressures; mounting territorial and sea disputes; and strained military relations. In addition, political instability in some border countries has had a significant impact on China's security situation. <<