a classic ex. of "mission creep". There was a poster here (can't recall) that laid it out nicely.
Something like we flooded troops into Tora Bora chasing bin Laden, and just wound up with Bush's war to secure and BUILD a stable Afghanistan.
Obama's problem is he doubled down on this unworkable idea - his so called "escalation/de-escalation" and got 3/4 of the total dead US troops under his watch killed.
Not to mention the $B's in aid.. Not to mention the fact Karzai makes him look foolish, etc.
Rumsfeld's original strategy for Afghanistan was to only have a small American footprint in Afghanistan. We didn't flood Tora Bora with troops.
You may remember back in 2004 the leading Democrat candidate for the Democrat nomination for President was a war hero :lamo who received numerous Purple Hearts for self-inflicted wounds and was awarded the Silver Star for shooting a fleeing VC in the back. He said he knew how to win in Afghanistan. Increase the size on special forces ten fold, you know, every soldier is a Green Beret and every sailor is a SEAL, Then flood Afghanistan with special forces. I don't know how many he was thinking of, 200,000 ?
By late 2001, Al Qaeda had fled Afghanistan moving their base of operations to Yaman and the Horn of Africa while those Al Qaeda who couldn't afford a pane ticket went into hiding in Northern Pakistan. Until 2009, Al Qaeda would be trapped and confined to these three regions.
By early 2002 the Taliban would get their butts whooped along with a broken nose, swollen black eyes and a few fractured bones and would flee to Pakistan to lick their wounds for years.
It ends up there were a few Taliban who were able to read and knew the history of Vietnam and some had internet access to see what Americans were saying. As soon as they saw the usual Americans back stabbing the American soldier in Iraq by not supporting the war in Iraq, the Taliban started reentering Afghanistan on snoop and poop missions. As soon as G,W. Bush became a lame duck President the Taliban started coming back to Afghanistan.
The Taliban biggest concern was who would win the Presidency in 2008 ? As soon as they saw that Obama who was Muslim friendly would win, the Taliban came back big time. The Taliban smelled victory in 2009 as soon as Obama said that he would be withdrawing American troops from Afghanistan before winning the war.
Should be noted that when the military commanders requested a troop surge in early 2009, it took Obama months to react. Obama would cave in and agree to send half of the number of troops that were requested and it would be over six months after the surge request was made before the first surge troops have started entering in-country. Then Obama introduced his politically correct Rules of Engagement (ROE) that favored the Taliban and would cause American troops to bleed in die in the name of political correctness.