The United States recently focused its efforts in Asia on improving trade with China and securing a denuclearization agreement with North Korea. While Washington correctly prioritized these important goals, it appears to be neglecting other pressing regional issues. These other issues include China’s increasing militarization of man-made islands in the contested South China Sea and its growing aggression towards Taiwan. The trouble is that these regional problems are interconnected, with Chinese gains on certain issues potentially irreversible. What this means is that the U.S. cannot myopically focus on only two of the many challenges it faces in Asia.

Following President Trump’s election, America has shown signs of taking tough positions on a range of security issues in Asia. For instance, consider the following examples:

First, Trump added $15 billion to his predecessor’s last military budget and proposed a ten percent increase in defense spending for the next year. In addition, much of this additional funding would bolster America’s missile defense and naval presence in Asia. In its first National Security Strategy (NSS), the Trump administration also called China a “revisionist power” and “strategic competitor.” Moreover, the NSS also pledged to halt China from remaking Asia in its favor, whereas the Obama administration emphasized cooperating with China.

Second, in January 2017, then Secretary of State nominee Tillerson declared that China should be denied access to the islands it has manufactured in the South China Sea. A third of the globe’s maritime traffic traverses those waters, where five countries plus China have competing claims. In 2017, Washington executed four freedom of navigation operations (FONOPs) to contest Beijing’s territorial claims in those waters. In eight years, the Obama administration conducted only six FONOPs there.

Third, American support for Taiwanese independence from China appeared to harden. In December 2016, then President-elect Trump accepted a call from Taiwan’s president, the first such call between that island’s leader and an American president or president-elect since the countries’ diplomatic ties and high-level contacts ended in 1979. In June 2017, President Trump also approved a $1.4 billion arms sale to Taiwan, whereas before leaving office, the Obama administration blocked a smaller arms package to that country. Furthermore, in December 2017, President Trump signed a defense funding bill with clauses suggesting port calls and military drills between the U.S. and Taiwanese navies.

But since Washington grew optimistic about its trade and denuclearization negotiations with Beijing and Pyongyang, it has appeared to neglect other pressing regional issues. For instance, China has recently deployed radar and communications jammers along with anti-aircraft and anti-ship missiles on its artificial islands in the South China Sea. The aim is to halt U.S. military operations and enhance China's territorial claims there. This year, China has also applied greater pressure on Taiwan, such as by cutting tourism to and trade with that country. Additionally, China encircled the island with fighter jets and an aircraft carrier group, compelled foreign airlines to refer to Taiwan as part of China, and convinced two of the island's dwindling allies to change their allegiance to China. Beijing seeks to punish Taipei for its pro-independence tilt. Unfortunately, the U.S. has not consistently and firmly responded to these troubling events.

The Trump administration may have put the South China Sea, Taiwan, and other issues on the backburner in the hopes of securing Chinese cooperation on trade and North Korean denuclearization. Presumably, the rationale is that by at least temporarily eliminating some friction between Washington and Beijing, China is more likely to find common ground on issues that the U.S. deems more important.

This approach is not unreasonable. Indeed, President Trump says that Beijing’s involvement helped Washington secure a preliminary pledge from Pyongyang “to work toward complete denuclearization of the Korean Peninsula.” (I will not assess here the value of that oft-repeated and broken promise.) Still, the approach poses risks.

First, most issues in Asia are interconnected given the hegemonic competition between the U.S. and China. As China seeks to replace America as the dominant power in Asia, weaker countries in the region are pressured to side with Washington or Beijing. This contest for allies often means that a win for one country is an automatic loss for the other, and that progress on one issue impacts an ostensibly unrelated matter.

For example, what if Beijing squeezed Pyongyang to sign and follow a denuclearization deal with Washington, but the U.S. had to ignore China militarizing islands or bullying Vietnam and the Philippines as the cost of Beijing’s assistance? This would mean that Southeast Asian countries sparring with China in those contested territorial waters are more likely to succumb to China in the future. After all, eliminating the North Korean threat benefits countries like Vietnam and the Phillippines little because Pyongyang’s nuclear weapons were not aimed at them. But Washington allowing Beijing to fortify its presence in contested waters near their coasts makes Southeast Asian countries feel they have to acquiesce to or else stand up to a significantly more powerful China possibly without American backing. In other words, the U.S. must avoid compartmentalizing issues.

Second, failing to contest China on specific issues—even temporarily—can give it irreversible gains.

For instance, Beijing will not withdraw the new weapons it has deployed in the South China Sea. Even worse, China will likely escalate its island militarization given the weak responses it has faced so far. U.S. inaction has thus permanently boosted Beijing’s military position and bid for regional supremacy. Indeed, the head of the U.S. Indo-Pacific Command recently deemed China “capable of controlling the South China Sea in all scenarios short of war with the U.S.”

The U.S. is right to seek improved trade with China (assuming that includes stopping China's theft of U.S. technology) and to eliminate North Korea's nuclear capabilities. But Washington must simultaneously progress on other challenges in Asia, irrespective of Beijing's reaction. Of course, the tempo and forcefulness of America's responses should be calibrated as the strategic landscape requires. This means the risks of American inaction on certain matters must be carefully considered before that approach is adopted as part of an exchange for purported Chinese cooperation on other issues. Moreover, as shown by Beijing's vacillating commitment to sanctioning Pyongyang—even after Washington let several Chinese transgressions on other issues slide—the U.S. should ensure that such cooperation is verifiable and tough to reverse before it makes concessions that are difficult to rollback.

Fortunately, the Trump administration may be changing course. With John Bolton as the new National Security Advisor, no threat in Asia will go unexamined. Indeed, the U.S. is considering sending a warship through the Taiwan Strait, and the same day that President Trump met with North Korea’s leader, Washington opened a new de facto embassy in Tapei. Days ago, the U.S. flew B-52 bombers through the South China Sea to contest China’s militarization there. The flyover followed Secretary of Defense Mattis accusing China of “intimidation and coercion” in the region, and confirming that the U.S. will “stay” in that “priority theater.” Secretary Mattis also recently rescinded China’s invitation to the world’s largest international naval drill (RIMPAC) and threatened “larger consequences” if China continues to militarize the South China Sea.

In addition to standing up to China more frequently, the U.S. must improve relations with its Asian friends. For example, partners’ confidence in America has ebbed since the Trump administration withdrew from the Trans-Pacific Partnership, imposed tariffs on Japan, threatened to end its free trade agreement with South Korea, and then offered to revive a failing Chinese telecommunications entity that illegally transferred American technology to North Korea and Iran.

Only if Washington assesses all opportunities and challenges in Asia collectively and understands their interplay can it execute the right strategy there.

Paul J. Leaf is a regular commentator on U.S. foreign policy. He worked on defense issues for a think tank and is now an attorney at an international law firm.