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For 16 years, the United States has tried to stabilize and rebuild Afghanistan with a goal of preventing the war-torn country from once again being used as a launching pad for international terrorism – as it was during the September 11 attacks.

But despite spending more than $600 billion and thousands of lives lost, American efforts in Afghanistan have largely fallen short of expectations and promises.

“The situation in Afghanistan is incredibly shaky right now,” said Lt. Col. Mike Waltz, a former Special Forces commander in Afghanistan and the Middle East. “We are essentially partnered with the Afghans. And the Afghans are losing slowly.”

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As the Trump administration mulls its next move, experts say both Iran and Russia are actively trying to move in to shape Afghanistan in its favor.

Experts say the two American foes are trying to exert their influence over Afghanistan’s future as the U.S. debates what the new strategy should be for the U.S. mission there. According to U.S. and Afghan officials, both countries have stepped up their contacts with insurgent groups and are even training and arming them.

The top U.S. commander in Afghanistan, Gen John Nicholson Jr., has repeatedly warned about both countries growing influence.

“Russia has become more assertive over the past year, overtly lending legitimacy to the Taliban to undermine NATO efforts and bolster belligerents using the false narrative that only the Taliban are fighting [ISIS],” Gen. Nicholson told the U.S. Senate Armed Services committee in February. “Similarly, neighboring Iran is providing support to the Taliban while also engaging the Afghan government over issues of water rights, trade, and security.”

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A few months later, one of the Pentagon’s top Generals issued a similar – though more tempered – warning.

"I believe what Russia is attempting to do is they are attempting to be an influential party in this part of the world," Gen. Joseph Votel, chief of U.S. Central Command, told American lawmakers in March. "I think it is fair to assume they may be providing some sort of support to [the Taliban] in terms of weapons or other things that may be there."

After initially losing territory during the surge of American troops six years ago, the Taliban is gaining ground in areas once controlled by the U.S.-led NATO coalition and Afghan security forces. ISIS has also established a foothold in several parts of the country, as well.

Insurgents have gained ground in the wake of President Obama’s decision to withdraw U.S. combat forces at the end of 2014. Both groups have launched a string of deadly attacks across the country this summer, and Afghan security forces have sustained huge losses among their ranks.

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Unlike, Afghanistan’s troublesome neighbor, Pakistan, which directly supports the Taliban, it is not clear the extent of Russia and Iran’s involvement with insurgent groups.

“We haven’t any indications that there are sanctuaries in Iran right now,” said Hamdullah Mohib, the Afghan Ambassador to the U.S. told Fox News, “But the ones in Pakistan continue to be a problem for Afghanistan.”

Pakistan has long been the chief supporter of the Taliban. Admiral Mike Mullen, former chairman of the U.S. Joint Chiefs of Staff, described the violent Taliban group, the Haqqani network, “as a veritable arm of Pakistan's Inter-Services Intelligence Agency,"

In order to deal with the growing problems in Afghanistan, the Pentagon has proposed sending roughly an additional 4,000 U.S. troops to train and assist Afghan Security forces.

"We are not winning in Afghanistan right now,” Defense Secretary Jim Mattis told Congress in June. “And we will correct this as soon as possible."

But the Trump administration, which promised a new strategy by the middle of July, is resisting that plan. Some in the White House, including President Trump, have questioned whether winning in Afghanistan is even possible.

Some security analysts are worried – given the deteriorating security situation – that the Trump Administration will simply walk away from the 16 years of American investment in Afghanistan.

“The stakes are high. What we can’t do is just walk away,” said Waltz, who argues that the troop number sent to Afghanistan is secondary, and not nearly as important, as a public statement of continued commitment from President Trump. “President Trump will then be to Afghanistan what President Obama was to Iraq.”

The White House is expected to announce a new policy in the coming days. Afghan officials hope it will be one of continued support.

“The United States and Afghanistan are fighting a common enemy,” Mohib said. “We have had a long partnership so far. We are hoping to be able to continue that.”