Editor's Note: (John McCain is a US senator for Arizona. Marco Rubio is a US senator for Florida. Ben Cardin is a US senator for Maryland. Jack Reed is a US senator for Rhode Island. The views expressed are their own.)
(CNN) On the heels of Secretary of Defense Jim Mattis' successful trip to South Korea and Japan last week, and with Japanese Prime Minister Shinzo Abe in Washington this week, we have an important opportunity to reaffirm America's commitment to security and prosperity in the Asia-Pacific region.
Seventy years ago, out of the ashes of a world war, America and our allies and partners built a rules-based international order -- one based on the principles of the rule of law, free peoples and free markets, open seas and open skies, and peaceful settlement of disputes.
Put simply: These ideas have changed the fortunes of the United States and Asia forever, and for the better. Our nation enjoyed access to resources that fueled broadly shared economic growth at home and a stability that kept another world war at bay, benefiting Americans from all walks of life, while an unprecedented era of peace and prosperity lifted hundreds of millions of Asians out of poverty and toward self-sufficiency.
None of this was preordained. And the rules-based order is not self-sustaining. America and our allies have made the choice to uphold and defend this order. We do so because it is profoundly in our national interest. And with challenges mounting from China's assertive behavior in the East and South China Seas to North Korea's increasingly dangerous nuclear threat, this is the stand we must take again. This is not just a choice for President Donald Trump. As a coequal branch, Congress must do its part to strengthen our alliances, deepen our diplomacy, and protect our interests.
A simple yet valuable first step would be to affirm America's broad, bipartisan commitment to defend our allies when they are threatened. Prime Minister Abe's visit is the right moment for President Trump and Congress to reiterate what Mattis asserted last week: that the Senkaku Islands are administered by Japan and therefore fall within the scope of Article 5 of the US-Japan Treaty of Mutual Cooperation and Security, and that the United States will oppose any unilateral attempts to undermine Japan's administration of these islands.
Our forward-deployed forces in the Asia-Pacific region secure our enduring national interests, uphold our treaty commitments, and safeguard open seas and open commerce. Fortunately, we also have allies that cover much of the cost of America's forward presence in the region. For example, Japan contributes approximately half of annual US basing costs, while South Korea contributes about 40%. But greater American investment is needed to update our posture and keep pace with evolving threats. A strong first step would be Congress' support for partner capacity building efforts to assure critical munitions, military facilities and strengthened cooperation with our allies.
Our military should continue to fly, sail and operate wherever international law allows, including where China's excessive and militarized maritime claims erode the freedom of the seas.
On the Korean peninsula, the administration must work with the South Korean government to assure a capable multilayer extended deterrence architecture, including accelerating the deployment of the Terminal High Altitude Area Defense, or THAAD, system to protect against North Korea's missile threat. Doing so is important for civilians threatened everywhere, from Seoul and Tokyo to Seattle, as North Korea prepares to test an intercontinental ballistic missile that can deliver a nuclear payload.
Our success in the region is not just based on military might, but on our values as well, and must also be matched by smart and agile diplomatic engagement and the full range of American influence. There are also significant opportunities to work with our allies and partners to deepen and broaden Asia's own emerging architecture, include the Association of Southeast Asian Nations, or ASEAN.
Finally, it is still imperative the United States engages economically in Asia. Five of our top 10 trading partners are in Asia and it is the destination for one-fourth of our exports. These relationships are more than statistics: They help American workers and businesses win access to new markets and new opportunities. To take advantage of them, the administration and Congress should work to open new markets in the Asia-Pacific region for American products, protect American invention and innovation, and support American jobs and manufacturing. We should welcome dialogue over investments in the United States that create jobs for our workers, build needed infrastructure and enhance productivity.
As a Pacific nation, the United States recognizes that much of the history of the 21st century will be written in the Asia-Pacific region. Now is the time to engage, not retrench. We stand ready to work with the administration to do just that.