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As Afghanistan continues to fall to the Taliban at a "faster-than-expected" pace, those who served in the war are reportedly "riveted in horror" watching the militant group make gains, and immensely frustrated by the withdrawal that's threatening to undo their 20 years of work, The Washington Post reports. 

"It makes me angry, really angry," said Tom Amenta, a retired veteran who was originally deployed in 2002. Afghanistan "has never had a clean solution," he told the Post. "But now that it's gotten hard, we're just going to bounce? It doesn't make it right."

The United Kingdom's Foreign Affairs Select Committee Chair Tom Tugendhat, who also served in Afghanistan, called the withdrawal "wasteful and unnecessary," adding that it's as though the rug has been pulled out from under the Afghan government.

"It's just frustrating," lamented Army veteran John Whalen. "We knew that this would happen. Now, all the people who went and served, are like, 'Why did my friend die?'" Whalen told the Post he asks himself that question, too.

Scott Novak, a former Army medic, added that, as the situation progresses, there's a "lingering sense of sadness" amongst his military friends. "No one's saying, 'Hey, you know, at least we did something.' There's just nothing to really show for it," he explained. "And so, everyone's kind of angry and wondering, why? Why were we even there?"