Tobi would've been screwed!!

[Uchiha Josephus]

He was talking about the army but other than that it was captured by the 1st Hokage (which you probably know) and to keep peace he distributed them to other villages, if you mean how Tobi got them it was buy sending members of the Akatsuki to captured the jinchuuriki not the tailed beast, the beasts were later extracted from them.

I am well aware of these facts. But I don't see how that means that an army (really, a few elite squads) can't take on the Bijuu ...

 

[Diottcas]

I am well aware of these facts. But I don't see how that means that an army (really, a few elite squads) can't take on the Bijuu ...

Yes sir, 5 tailed beast, gedo mazo, Tobi, 100,000 zetsus, and Sasuke > Army so easily

 

[Akatsuki wise guy]

Yes sir, 5 tailed beast, gedo mazo, Tobi, 100,000 zetsus, and Sasuke > Army so easily

really gaara and onoki sand and dust release could take the tailed beasts.
if the raikage could snap the horn of the second strongest tailed beats in one hit i think it could take some tailed beats. choji as he is is strong enough to take a beast not saying win but take one. the nara can make excellent battle plans that help. i wont list all but i think your underestimating the shinobi alliance.