0 news up >> tonight, new vaccine mandates spark legal scrutiny and push-back. >> the near term, you can discourage vaccination. >> millions are order to get their shots to curb the covid crisis that killed 650,000 americans. the latest cases causing concern for parents, kids back in school. >> i'm concerned for our kids. they are being used as political pawns in this chess game. that is reprehensible. >> we'll have a checkup on the issues with our dr. david agus. tonight, secret no more. the fbi declassified the documents examining the saudi government's role in the 9-11 attacks. and 20 years in the war on terror. cbs news is on the front lines of another al-quaida strong hold. california countdown, with two days to go, the race to recall governor newsome intensifies. later, the plane people. we remember the sanctuary provided to thoses during the country's darkest hours. >> good evening. thanks for watching. it's been a weekend of somber remembrances as america marked 20 years since the 9-11 attack. more on that in a moment. we begin tonight with a country still reeling from the effects of the pandemic. new daily infections are still high. trending down over the last two weeks. u.s. deaths are up. 30% over that same time period. meanwhile, president biden is doubling down on efforts to turn the tide against the virus. cbs's lilia luciano has details. >> good evening. there's praise and push-back over the president's new mandate. affecting companies like costco. requires with businesses with 100 employees or more to get vaccinated or test weekly for covid. president biden's sweeping new vaccine mandate appears to be deeping america's political divide. several republican governors including nebraska's governor pete ricketts are vowing to fight it. >> you shouldn't have to make a choice. >> the federal government is demanding workers and military gets the shots and some private businesses too. scott gottlieb. >> i don't think the federal government should dictate this and governors shouldn't make them make them do it. >> 80 million private sector workers are impacted. >> i think putting the onus on each individual employer is a lot of effort and to enforce it. having a consistent policy is a really good thing. >> half of all states have at least half their population fully vaccinated. nationwide, deaths are up. hospitalizations and cases are trending down. >> how do other parents, how are they okay with that? how are they okay with that? over a mask? >> for the kids sickest with covid, hospitalization rates spiked almost ten fold since late june. >> the reality is that we may be headed to another peak or to another valley if we all pull together. >> the vaccines that are available are for people 12 years old or older. according to dr. scott gottlieb, a vaccine for children between the ages of five and 11 may become available by halloween. >> lilia luciano, thank you. we turn to our cbs news medical contributor, dr. david agus. you just heard the mandates going into effect. how quickly do you think we'll see a difference? will the mandates work? >> they have to work. they're the most aggressive step mandating every federal employee and federal contractor as well as healthcare worker are vaccinated. 80 million people either will have to have a vaccine or a weekly test that work for companies with more than 100 people. unfortunately, there's no other way to get above the low 50%, which is where we are now in terms of vaccinating the country. we're the lowest of the g-7 countries. japan has passed the united states. we have to take drastic measures to get the vaccination up in the united states. >> we keep hearing about the mu variant. is that something to be concerned about? what is it? >> it originated in columbia in january. it's here in the united states in 49 of 50 states. it peaked about seven, eight weeks ago. it's lower now in terms of incidents across the country. we think convenience are working. so it's something that we're keeping an eye on but no worried to be worried at the present time. we're going to follow it daily. >> good news recently tcdc noted that having the vaccines prevents hospitalizations and deaths. with that type of information, do you think it will change the minds of people who continue to refuse to be vaccinated? >> you know, i hope so. unfortunately many of them it's their belief system, not data. as we get more and more data that are compelling that the vaccines work, they prevent serious illness almost uniformly and at the same time a remarkably safe thing, it has to step up our vaccination rate. i sound like a broken record but we have to do it. >> dr. agus, we appreciate the information. an explosion tore through an apartment complex in dunwoody georgia today, 20 miles north of atlanta. police arrived to the smell of heavy gas fumes. several people were trapped. one person was rushed to the hospital with injuries. today a fallen marine killed in a bombing in afghanistan's kabul airport returned to his indiana hometown. thousands lined the streets of logansport in honor of 22-year-old humberto sanchez. he was among the 13 u.s. service men and women killed in the attack and the final days of the u.s. withdrawal from afghanistan. the fbi has released the first of what are expected to be several documents into whether the saudi government supported the 9-11 hijacker's plot. at the same time, president biden is defending his afghan withdrawal. >> good evening. late last night, the fbi released a newly declassified document from 2016. the report shows a closer than previously known link between two saudi citizens living in the u.s. and the 9-11 hijackers including meetings and phone calls. the report does not prove a link with higher echelons of the saudi government. >> it's already back other places. what is the strategy? every place where al-quaida is, we're going to have troops stay there? come on. >> speaking to reporters in shanksville, pennsylvania, the crash side of one of the planes on 9-11, president biden defended the withdrawal of the place that hey bored the terrorists. >> 70% people say they favored getting out but they didn't like the way we got out. >> a cbs news polls say that most americans oppose using the u.s. military to create democracies. former acting cia director michael morell says not having a presence in afghanistan puts america at greater risk. >> you have safe haven in afghanistan that you can't have anywhere else. you're being harbored by the taliban now and afghanistan is a big place. it's tough to get to. it's tough to find partners. >> tomorrow secretary state anthony blinken will appear on the hill the first time since the u.s. left afghanistan to field what will be surely pointed questions from lawmakers on both sides of the aisle. >> thanks, christina. thank you. 20 years in the war on terror, the fight continues in countries far from afghanistan. holly williams recently joined yemen's military on the front lines. a civil war is underway and al-quaida is using the country as a base for attack. >> yemenese soldiers took us to the front line where they're fighting a war for this barren dessert. these are government forces. battling rebels that seized the capitol and swaths of land. there's been back and forth from both sides. these men are saying that their enemy is about 500 yards in that direction. the saudi arabian government is backing the yemeni government. they accuse iran of helping the rebels. the conflicts killed 250,000 people. some victims of starvation according to the u.n. in the anarchy, al-quaida has thrived here. the most dangerous, despite years of u.s. drone strikes. al-quaida's yemen branch train the manned that attempted to down a u.s. airliner in christmas day in 2009 with explosives sewn into his under pants and claims responsibility for a tearist shooting in paris that killed 12. sultan al arada is the governor of yemen's northern marib province. >> what would it take to get rid of al-quaida in yemen? >> we need a state. if we had a functioning government, we could clean them out. more than four million yemenese have fled their homes. many ending up in camps like this one. abdullah says he wants to be a doctor when he grows up. as long as the war rages, there's little hope for their future. the desperation that al-quaida feeds off of. holly williams, cbs news, marib, yemen. >> straight ahead on the cbs weekend news, a california recall puts governor newsome's pandemic leadership to the test. a small minnesota town cries foul over business ball's business moves. and a story of inspiration.