United States President Joe Biden said on Monday that he stands "squarely behind his decision" to withdraw American troops from Afghanistan as he blamed the Afghan leadership for giving in to the Taliban without any fight.
He also warned the Taliban of swift and forceful response from the US if they attack American personnel or disrupt their operations in Afghanistan.
He said if the Taliban interfered with the US military's evacuation operations in Afghanistan, the US would respond with devastating force.
"As we carry out this departure, we have made it clear to the Taliban, if they attack our personnel or disrupt our operation, the US presence will be swift, and the response will be swift and forceful," Biden said in his address to the nation.
"We will defend our people with devastating force if necessary. Our current military mission was short in time, limited in scope, and focused on its objectives: get our people and our allies as safely and as quickly as possible," he said.
Biden described the images coming out of Afghanistan as "gut-wrenching".
"I stand squarely behind my decision. After 20 years, I've learned the hard way that there was never a good time to withdraw US forces. That's why we're still there. We were clear-eyed about the risks. We planned for every contingency. But I always promised the American people that I will be straight with you," Biden said in his address to the nation.
"The truth is, this did unfold more quickly than we had anticipated. So, what happened? Afghanistan political leaders gave up and fled the country. The Afghan military collapsed, sometimes without trying to fight. If anything, the developments of the past week reinforced that ending US military involvement in Afghanistan now was the right decision," the US president said.
WATCH: I stand squarely behind decision to withdraw US forces, say Biden
He said American troops cannot be dying in a war that Afghan forces are not willing to fight for themselves.
"We spent over a trillion dollars. We trained and equipped an Afghan military force of some 300,000 strong. Incredibly well equipped. A force larger in size than the militaries of many of our NATO allies,” he said.
"We paid their salaries, provided for the maintenance of their air force, something the Taliban doesn't have. The Taliban does not have an air force. We provided close air support. We gave them every chance to determine their own future. We could not provide them with the will to fight for that future,” Biden said.
Coming back to the White House from the presidential resort of Camp David in Maryland, he said the US gave them every tool they could need.
"There are some very brave and capable Afghan special forces units and soldiers. But if Afghanistan is unable to mount any real resistance to the Taliban now, there is no chance that one year, one more year, five more years, or 20 more years of US military boots on the ground would have made any difference,” he said.
"And here's what I believe to my core. It is wrong to order American troops to step up when Afghanistan's own armed forces would not. The political leaders of Afghanistan were unable to come together for the good of their people, unable to negotiate for the future of their country when the chips were down,” he added.
Recalling his meeting with Afghan President Ashraf Ghani and Chairman Abdullah at the White House in June and telephonic conversations in July, Biden said, "We talked about how Afghanistan should prepare to fight its civil wars after the US military departed, to clean up the corruption in government so the government could function for the Afghan people."
"We talked extensively about the need for Afghan leaders to unite politically. They failed to do any of that. I also urged them to engage in diplomacy, to seek a political settlement with the Taliban. This advice was flatly refused. Ghani insisted that the Afghan forces would fight. But obviously, he was wrong,” he said.
Biden asserted that he will not repeat the mistakes the US has made in the past, mistake of staying and fighting indefinitely in a conflict that is not in the national interest of America, of doubling down on a civil war in a foreign country, of attempting to remake a country through the endless military deployments of US forces.
"Those are the mistakes we cannot continue to repeat because we have significant vital interests in the world that we cannot afford to ignore,” he said.
”I also want to acknowledge how painful this is to so many of us. The scenes we're seeing in Afghanistan, they're gut-wrenching, particularly for our veterans, our diplomats, humanitarian workers, for anyone who has spent time on the ground, working to support the Afghan people, for those who have lost loved ones in Afghanistan, and for Americans who have fought and served in the country, serve our country in Afghanistan,” he said.
WATCH: Biden warns Taliban of forceful response if US personnel are attacked
He vowed to complete the planned withdrawal of US military troops in Afghanistan.
"And once we have completed this mission, we will conclude our military withdrawal. We'll end America's longest war after 20 long years of bloodshed. The events we're seeing now are, sadly, proof that no amount of military force would ever deliver a stable, united, secure Afghanistan. As known in history, it's the graveyard of empires," he said.
Biden said what's happening now could just as easily happen five years ago or 15 years in the future.
"You have to be honest. Our mission in Afghanistan is taking many missteps, made many missteps over the past two decades. I'm now the fourth American president to preside over the war in Afghanistan, two Democrats and two Republicans,” he said.
"I will not pass this responsibly down to a fifth president. I will not mislead the American people by claiming that just a little more time in Afghanistan will make all the difference, nor will I shrink from my share of responsibility for what we are today and how we must move forward from here," he said.
The US president said he is saddened by the current situation in Afghanistan, but does not regret his decision to withdraw American troops.
"I am president of the United States of America, and the buck stops with me. I'm deeply saddened by the facts we now face, but I do not regret my decision to end America's warfighting in Afghanistan and maintain a laser focus on our counterterrorism mission there and other parts of the world. Our mission to degrade the terrorist threat of al-Qaeda in Afghanistan and kill Osama bin Laden was a success," he said.
Biden said he will not ask his troops to fight on endlessly in another country's civil war, taking casualties, suffering life-shattering injuries, leaving families broken by grief and loss.
"This is not in our national security interest. It is not what the American people want. It is not what our troops, who have sacrificed so much over the past two decades deserve. I made a commitment to the American people when I ran for president that I would bring America's military involvement in Afghanistan to an end," he said.
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