Taiwan should prepare to deter a Chinese invasion, White House national security adviser Robert O’Brien said Friday.”I think Taiwan needs to start looking at some asymmetric and anti-access area denial strategies and so on and really fortify itself in a manner that would deter the Chinese from any sort of amphibious invasion or even a gray zone operation against them,” O’Brien said at an Aspen Institute event.A gray zone operation, he added, might include isolating the island economically. The term refers to coercive and provocative actions short of the use of military force.Some analysts say China could move against Taiwan should the U.S. presidential election result in political chaos, Reuters reported.China has maintained that Taiwan is part of China and that it should be reunited with the mainland, even by force.FILE – National security adviser Robert O’Brien speaks during a press briefing at the White House in Washington, Sept. 4, 2020.While advocating preparation, O’Brien said he didn’t think the Chinese ”want or likely are prepared for an amphibious landing” on Taiwan.“It would be a hard operation for the Chinese to do” and Beijing would have to consider how the United States would respond, he said. “If we got involved, that can make that a very dangerous effort for the Chinese to engage in.”He did say China was capable of annihilating Taiwan with a massive missile attack, but that he didn’t know what they would gain from it.He also said a gray zone operation would rile most of the Asia-Pacific region and isolate China internationally.FILE – The guided-missile destroyer USS John S. McCain approaches Da Nang, Vietnam, May 7, 2019.Tensions in the region have been growing.In response to Chinese saber-rattling, a U.S. warship transited the Taiwan Strait on Oct. 14. The transit came nearly a week after China warned another U.S. ship, the USS John S. McCain, near the disputed Parcel Islands in the South China Sea.Zhang Chunhui, a spokesman for China’s eastern theater military command, said in a statement that China monitored the USS Barry’s movements earlier this week, according to Reuters.Beijing, for its part, has been ramping up air force activity near Taiwan. It also has ramped up the rhetoric, accusing the U.S. of “collusion” in trying to push the island nation to declare formal independence, Reuters reported.The U.S. is trying to bolster Taiwan’s defensive posture by selling it military equipment, including sophisticated drones and a coastal defense missile system.