WASHINGTON: Noting that the world order faces challenges from Russia, terrorist elements and China, US Defence Secretary Ashton Carter today said that though none of them can overturn it completely but they are intent on undermining its values."Today, the rules-based international order faces challenges from Russia, terror elements, and, in a very different way, China," Carter said in his address to the Woodrow Wilson Center before leaving on a trip to Asia."None of these actors can overturn it completely, but they are intent on undermining some its values and undercutting some of its effectiveness. We won't let them," Carter said."And to meet these challenges, we need the right strategies. Strategy now is about perspective. It means understanding where our challenges today fall in the context of history and how we can use history's lessons to pursue today's opportunities," the Defence Secretary said."It means knowing which mix of foreign policy tools is best for a given situation. And it is about keeping focused on our interests, they're our North Star in the Asia-Pacific, in Europe, and in the Middle East," he said.Referring to his travel this week to Asia, Carter said he will continue to work to build a shared regional architecture that is strong enough, capable enough, and connected enough to ensure that all Asia-Pacific peoples and nations, whether large or small, have the opportunity to win to rise, to prosper, and to determine their own destiny."As Secretary of Defence, I am working hard on the next phase of our rebalance to the region, in which the Defence Department is deepening long-standing alliances and partnerships, with South Korea, Japan, Australia, and India, and is diversifying America's force posture, making new investments in key capabilities and platforms, and building new partnerships with countries like Singapore and Vietnam ," Carter said.He said the US is finalising the Southeast Asia Maritime Security Initiative, which will build greater regional capacity to address maritime challenges."And we're continuing our maritime exercises and engagements, such as the Southeast Asia Co-operation and Training, or SEACAT, maritime exercise with six ASEAN countries, including Brunei , Indonesia, Malaysia, the Philippines, Singapore, and Thailand," he said."Many nations in the Asia-Pacific want to work with us, and we want to work with them too," he said adding that one reason for that is because US is taking a stand for freedom of navigation, one of the rules and customs that have helped so many nations in the region rise."We're making it clear, that the United States continues to favour peaceful resolutions to ongoing disputes, and that we will continue to fly , sail, and operate whenever and wherever international law allows," he added."We mean what we say. The South China Sea is not - and will not - be an exception," Carter said.