What's stopping them from destroying Arabasta? Or Dragon's island? What's the line that has to be crossed?

[Warmmedown]

Why not just wipe it off the map, if Vivi is causing problems? Does he want to preserve Arabasta for sentimental reasons?

What was the line crossed before Islands were destroyed? One was because of the slave hunting game. What about the other one? And why not destroy Dragon's island? Could he?

 

[SSJ2]

Are you talking about Imu? It seems like they are heading in that direction after testing out the mother flame on Lulusia Kingdom. I don't know how they destroyed God Valley or other islands prior to having the ancient weapon functioning though.

 

[Warmmedown]

Yeh Imu.

They wiped God Island off the Earth without the same weapon? Ohara wasn't destroyed right? It was levelled but I guess the island still exists? Or could a buster call itself destroy it? Even if they destroyed the top of it enough to make it all below sea level it would still show up on a log pose.

If lots of cannon fire, an admiral and some vice admirals (ie a buster call) isn't enough they could have destroyed God Island with Whitebeard's power, but they never controlled him.