Currently bitcoin has 53 Exahashes while bch has 3. A 51% attack would need 1.5EH+. That is something that quite a few actors in this space has available. Rewriting or grinding the BCH
chain to a halt is dangerously feasible.
This is unrealistic but as a comparison it would take the current
btc hashrate just 25 days to completely rewrite (IE double spend or whatever shenanigans) the entire bch chain since the fork.
