Editor's note: Xin Ping is a commentator on international affairs, writing regularly for CGTN, Global Times, China Daily, and other media outlets. He can be reached at xinping604@gmail.com. The article reflects the author's opinions and not necessarily the views of CGTN.

The Colorado River and the Rio Grande flowing between the United States and Mexico form much part of their boundary. Their limited flow is no parallel to the Mississippi, but they are undeniably lifelines to the arid border area on both sides. The waters are more precious than gold to Mexico, where more than half of its provinces are arid.

However, the U.S. showed little understanding or generosity to its neighbor. The disputes over the distribution of the transboundary waters go way back and necessitated binational treaties, which explicitly favor the U.S. 

The one in 1906 mandates U.S. water allocation to Mexico via the Colorado River and Mexican provision to its northern neighbor via the Rio Grande. Though the sharing obligation falls on both sides, the burden and requirement are not actually reciprocal. The U.S. is allowed to reduce water delivery in drought years, and the reductions do not accumulate as a water debt to be paid up later. No similar flexibility for Mexico was included.

The other treaty in 1944 gave the seven U.S. states in the south 90 percent of the water share from the Colorado River, leaving a meagre 10 percent to downstream Mexico. Meanwhile, Mexico must give the U.S. a minimum of 430 million cubic meters of water annually from the Mexican tributaries of the Rio Grande without exception. It turns out, sadly, the treaty failed to foresee how scarce water could be 70-plus years later. Now, there is simply not enough water for Mexico to meet U.S. demand. Due to climate change, sustained dry-ups in the middle-lower Rio Grande since the 1990s means less Mexican water flows to the U.S. In other words, by sticking to the plan benefiting itself, the U.S. is taking away the water Mexicans rely on for living.

Apart from the texts, the 1944 treaty lacks a spirit of compromise and common development throughout U.S. negotiation. The U.S. only started to respond to Mexico's protests after it settled the contention for water rights among its seven southern states. It threw out an ultra-highball in disregard of Mexico's need for water. When the talks fell into deadlock, the U.S. moved on to gain more leverage by changing the status quo. By 1935, the country planned and built almost 10 dams including the Hoover Dam and the Grand Valley Diversion Dam on the Colorado River. In 1942, the country built the All-American canal, bypassing Mexico to directly supply its own cities and regions. The projects resemble water taps that change the flow and cycle of the waters, giving absolute control and "water hegemony" to the U.S.

"Poor Mexico, so far from God, so close to the U.S." The words of late Mexican President Diaz come to mind every time Mexico faces economic and political pressures, including those on water rights, from its northern neighbor. North Mexico heavily relies on the U.S. in terms of irrigated agriculture and water-dependent manufacturing industry, especially so after the North American Free Trade Agreement (NAFTA) was signed in the 1990s. The U.S. over-exploitation and usage of the water upstream has devastated ecology of the lower reach of the Colorado River. It has not flowed into the sea since 1998, with its estuary has suffered chronic dry-up of delta and significant shrinkage of wetlands. After irrigation in the U.S., the return flow of the river water dwindles in amount and becomes highly salinized, causing soil salinization and reducing agricultural production in Mexico.

The ongoing tension over water between the U.S. and Mexico reminds people of the remarks by the U.S. Vice President Kamala Harris just months ago, "For years there were wars fought over oil; in a short time there will be wars fought over water." For all the frankness, she needs to do her homework – the U.S. has control over water without fighting a war with its neighbor Mexico.

Be it a mantra or a convention, "America first" is zero-sum that allows little development opportunities for others, including water distribution. If the U.S. believes in "loving thy neighbor," if it equally cares about human rights of each and every person, now it's time for it to let water flow into Mexico.

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