I guess though air is available everywhere still its the weakest element if no then why were the people nkt able to savd them from fire nation

The air nomads are a peaceful people, who believe(d) in isolation and non-violence. They had no quarrels with any of the other elemental groups, and had no means with which to defend themselves. The fire nations attack was sudden and unexpected, which is why the air nomads were so defenseless. It has nothing to do with weakness.

Did you pay attention to the series at all? There's no weaker or stronger element of the 4 main bending styles. Doing Sozin's comet the Fire Nation was extremely strong thanks to that. Other than that they couldn't take down the Air Nomads by themselves. And if you realized they needed the comet to come around again to fully take over the world. It just so happens Aang and everyone was there to stop it this time around.

There Is No Weaker Or Strongest Element. Each Of Them Has It's Unique Characteristics. The Element Of Air Doesn't Specialize In Attack But In Evasion And Speed. The Air Nomads Are Pacifists. They Will Not Fight To Kill, Only To Protect Themselves And Those Around Them. Of Course That Doesn't Mean That An Airbender Cannot Win Against Another Type Of Bender. During The Fire Nations Invasion On The Southern Air Temple, Monk Gyatso, An Experienced Airbender Was Able To Take Down Hordes Of Comet-Enhanced Fire Nation Soldiers Before His Demise. There Are Also Many Other Examples Of How Powerful The Element Of Air Can Be. For Example Avatar Aang And If You Have Watched The Legend Of Korra, Tenzin And Zaheer. Finally About The Fire Nation's Invasion Don't Forget That Firebenders Had Their Abilities Greatly Enhanced By The Sozin's Comet At That Time !!!!

i dunno i guess that's the way it is but it makes sense because fire benders get the power of the sun

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