[marcosdumay]

My guess is that the lack of liquidity is protecting the coins from the attack. You can't get much money out of most markets on 1 hour.

What is quite ironical, because if any of them just become a useful currency, that means it would get instantly attacked and worthless.

[Zpalmtree]

As there usefulness increases so does their price and subsequently hashpower and volume, making 51% attacks harder to perform.

[marcosdumay]

If you look at the table, it's shorting even Bitcoin and then attack it.