Troops from the US, Japan, the UK and France are reportedly gathering in Guam and Tinian for drills on Thursday, a military exercise that Chinese experts said is political rather than tactical, and aims to demonstrate unity on security issues.The drills "will show support for the free passage of vessels in international waters and "may also send a message to North Korea of US commitment to the region and its allies," the Associated Press reported on Tuesday.Tensions between the US and North Korea spiked last month after Pyongyang tested a ballistic missile and the US sent an aircraft carrier strike group to the region."The main purpose of the military exercise is political rather than tactical. France and the UK sent vessels and troops to the drill to show that the West is united on security issues," Xu Guangyu, a senior adviser to the China Arms Control and Disarmament Association, told the Global Times on Thursday.The drills include amphibious landings, helicopter airlifts of troops and urban patrols. Two ships from France are participating, both of which are in the middle of a four-month deployment to the Indian and Pacific oceans. UK helicopters and 70 UK troops are deployed in the French amphibious assault ship FS Mistral, AP reported."The situation on the Korean Peninsula remains intense, and the US, as the leader of NATO, invited two major European NATO members to practice amphibious landings to send a strong message to North Korea," Song Zhongping, a military expert who used to serve in the PLA Rocket Force, told the Global Times on Thursday."The US encourages NATO to take on greater responsibilities, and it also wants to show that, in the event of a military conflict on the peninsula or in other places in the Asia-Pacific region, the US will not only receive support from its Asian as well as European allies," Song said."The message we want to send is that we're always ready to train and always ready for the next crisis and humanitarian crisis wherever that may be," US Marine Corps Lt. Col Kemper Jones, the commander of the 8th Marine Regiment's 3rd Battalion, said. About 100 Marines from Jones' unit will be part of the drills this weekend and next week, AP reported.AP also cited David Santoro, a senior fellow for nuclear policy at Pacific Forum CSIS, a Honolulu think tank, as saying that the exercises come amid modestly growing European interest in the South China Sea.However, Xu said that the drills in Guam only involve 700 troops. So tactically, it's meaningless either for the Korean Peninsula or the South China Sea issue.