[Question] Why didn't the Revolutionary Army support the Whitebeard pirates?

[Olorin]

I know, but why did Luffy need to be there for Sabo to go? If he wanted too... I think it's because the Revolutionaries have put too much effort into there plans to lose members at the battle.

The OP asked why didn't Sabo AND Dragon go

 

[MugiwaraBoy]

The OP asked why didn't Sabo AND Dragon go

Dragon was most likely friends with Roger from Theories and stuff I have seen, plus if Sabo is his second in command why wouldn't he want to help him? he obviously knows how far him luffy and ace go... but yeah I think they didn't want to expose themselves and lose troops.

 

[Fireplay]

Why would they? Dragon is the one calling the shots and he most likely doesn't give two shits about Ace. He wouldn't risk everything to save some pirate that he's never met. Saving Ace was WB's crews job. Dragon isn't Superman. He doesn't show up and save the day.

 

[Bogard]

The war was transmitted all over the world. If revolutionary helped pirates, they would have lost fate over the world

 

[Sanzen]

While they are against the world government, they can't be seen helping pirates, it would ruin any credibility that they had.
It's as simple as that.