Pakistan held its annual military day parade and displayed its new medium-range nuclear missiles last month, and it barely made a splash in Washington. But at least one analyst was paying close attention.Richard Fisher, an expert on Chinese military technology at the International Assessment and Strategy Center, began studying the public satellite photographs of the Shaheen III missiles and came to an alarming conclusion: The transport-erector-launcher, or TEL, for the Pakistani mobile rocket matched a Chinese design that Beijing had exported in 2011 to North Korea.Specifically, Fisher found that the Chinese, North Korean and Pakistani TELs shared the same foothold shape, the same chassis slope and the same exhaust processing system over the engine compartment.Now, two leading Republicans in Congress are asking the Pentagon, the State Department and the director of national intelligence to look into Fisher's findings. I obtained a copy of the letter from Representative Mike Rogers of Alabama, chairman of the House Armed Services subcommittee on terrorism and strategic forces, and Ted Poe of Texas, chairman of the House Foreign Affairs subcommittee on nonproliferation and trade.Poe and Rogers are alarmed. While China and Pakistan have cooperated on military technology for decades, and China's government announced in 2013 it would be assisting with the construction of nuclear power plants in Karachi, the extent of China's cooperation with Pakistan's nuclear weapons program has always been murky. Since the 1980s, the U.S. government has had its suspicions that China assisted Pakistan's nuclear weapons program. But U.S. presidents have also certified publicly since the 1980s that China was not a nuclear proliferator.If Fisher's research is confirmed, then it would be evidence that China has been assisting Pakistan's nuclear program and continues to do so to this day."We are deeply concerned that the TEL displayed in Pakistan was acquired from China," Poe and Rogers wrote to Secretary of State John Kerry, Secretary of Defense Ashton Carter and Director of National Intelligence, James Clapper. "The transfer of an item as advanced and significant . . . would require the approval from the highest levels of China's government if not also the People's Liberation Army. Such cooperation between the governments of Pakistan and China would represent a threat to the national security of the United States and its allies."A spokesman for the Office of the Director of National Intelligence declined to comment Monday.In a letter to Poe and Rogers summarizing his findings, Fisher wrote that if his research is confirmed, it would be grounds to seek new sanctions against China at the United Nations, and would trigger the enforcement of existing U.S. sanctions. He also said that it's a threat in and of itself if China is exporting such equipment or even the design of such technology, because it could end up in North Korea, which in turn could re-export it to Iran.This is the kind of diplomatic problem President Barack Obama would likely want to avoid in the final months of his presidency. After all, despite his protests and promises to refocus America's defensive posture to the Pacific Ocean, the Chinese have moved ahead with plans to militarize islands it built up in the South China Sea. But the rest of the world may not be able to wait this long. The new Pakistani missiles have a range of 1,700 miles, which would cover all of India. If China helped Pakistan with the technology for these weapons, it raises the question what other nuclear programs China is willing to assist.(Bloomberg View columnist Eli Lake writes about politics and foreign affairs.)© 2016 Bloomberg L.P.