• Mine would supply over a quarter of US copper needs
• Strong Native American, environmental group opposition
• Supreme Court appeal filed to block mine access
• 2024 presidential election outcome could determine mine's future
• Arizona is one of a few states likely to decide the election

Sept 12 (Reuters) - Native American opposition to Rio Tinto (RIO.L) , opens new tab(RIO.AX) , opens new tab and BHP's (BHP.AX) , opens new tab Resolution Copper mine could prove crucial for the 2024 U.S. presidential vote in the battleground state of Arizona, underscoring the high tension over where best to extract critical minerals for the energy transition.

The mine would, if built, supply more than a quarter of America's appetite for copper and be a key part of Washington's efforts to eat into China's role as the world's largest copper processor and consumer.

The U.S. imports nearly half of its copper needs, according to the U.S. Geological Survey, and its copper mine production has dipped 11% since 2021. There are only two domestic copper smelters.

Yet the underground Resolution mine would cause a massive crater that would swallow a religious site where Arizona's San Carlos Apache worship. That has fueled strong opposition from all but one of the state's 22 Native American tribes, as well as the National Congress of American Indians.

An appeal was filed on Wednesday asking the U.S. Supreme Court to block Rio and BHP's access to the land, which Congress and President Barack Obama approved in 2014 after it was added at the last minute to a must-pass military funding bill with the condition that an environmental report be published. President Donald Trump published that report in 2021, days before leaving office, a move that was reversed two months later by his successor, Joe Biden.

It is unclear whether the Supreme Court will take the case and, if it does, how or when it could rule.

Whoever wins the Nov. 5 U.S. election will be able to either approve the mine or keep its development essentially frozen, the step that Biden took after Arizona's 400,000 Native Americans - nearly 5% of the state's population - helped deliver him and then-running mate Kamala Harris the state and thus helped him win the White House in 2020, according to exit polling that year.

In the 2024 presidential race, Republican Trump narrowly leads Harris, the Democratic nominee, among registered Arizona voters in a Reuters/Ipsos poll published on Aug. 29. Arizona is one of a handful of states likely to decide the election.

Native Americans have tended to vote Democratic in the past, but many tribes in the U.S. Southwest have cited climate change and the economy as key issues for them this year.

The San Carlos Apache and others are now flexing their electoral muscle once again, pushing Harris to block the mine if elected.

"We definitely expect Native votes to be the determining factor in Arizona," said Wendsler Nosie, head of the Apache Stronghold, a nonprofit group comprising of the San Carlos Apache and conservationists. "All Native people are watching this issue, because this sacred space is the heart of who we are."

The Harris campaign did not respond to requests for comment.

Harris in 2020 told Arizona's Native American tribes they would have a "seat at the table" if she and Biden were elected. The San Carlos Apache then made a successful appeal to Harris in 2021 to block Resolution, tribal officials told Reuters.

Harris has said little about critical minerals on the 2024 campaign trail, and her aides have told Reuters she intends to be strategically ambiguous on energy-related issues.

In a statement to Reuters, Halee Dobbins, the Republican National Committee's Arizona communications director, said Trump sees energy independence as a key concern for Native Americans and believes "Democrats have been hard at work destroying our energy supply," although she did not directly address the Resolution project.

"Team Trump in Arizona has been dedicated to uplifting the Native American people and addressing the unique challenges facing their communities," said Dobbins.

Trump has been supportive of most mining projects and said he would take steps that would support Antofagasta's (ANTO.L) , opens new tab controversial Twin Metals project in Minnesota "within minutes" of a second inauguration. Biden and Harris killed that project in 2022.

Some members of Trump's campaign have spoken in favor of Resolution, although he has not yet spoken about it publicly in this election cycle.

That largely pro-mining stance from Trump - and Harris' support for the Inflation Reduction Act and other climate-linked policies - has not gone unnoticed in the state, tribal activists say.

"Mobilizing the Native vote is so important in Arizona," said Gunes Murat Tezcür, a political scientist at Arizona State University. The Resolution project "is going to be a big issue for the San Carlos Apache."

DIALOGUE

Rio Tinto, which plans to keep Resolution's copper in the U.S. if the mine is built, said it has been trying to expand ties with the state's tribes, including by supporting food banks after recent deadly wildfires. Fifty of Resolution's employees are San Carlos Apache.

"We continue the dialogue and agreement-making with tribes," said Vicky Peacy, who runs Resolution for Rio. The company declined to comment on the U.S. election.

BHP, which owns 45% of the project to Rio Tinto's 55%, declined to comment.

Steve Trussell, head of the Arizona Mining Association trade group, said he worries U.S. imports of copper will increase if Resolution is not developed and noted that China has already begun blocking exports of other critical minerals used in the climate fight.

"We'll fall further behind on clean energy and addressing climate change, which would disproportionately hurt Arizona's small towns and Native American communities more than most," he said.

It is that tension that is front of mind for Mila Besich, the Democratic mayor of Superior, Arizona, the town closest to the Resolution project. Besich, who has endorsed Harris but also supports Resolution, has been lobbying Harris' team to support the mine.

The same 2014 law that approved the federal land swap with Resolution also gives Superior access to land for economic-development projects, a key appeal for Besich in a town with a 45% unemployment rate. Besich said she has not received any commitments from the Harris campaign yet, but plans to keep pressing the issue in the coming weeks.

"I'm very hopeful that as we ramp up this campaign, that the Resolution project gets the attention it deserves," said Besich. "It's starting to resonate just how important it is."

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https://www.reuters.com/markets/commodities/arizonas-battle-over-crucial-copper-mine-poised-sway-us-election-2024-09-12/