Preventing people from committing horrible acts is an impossibility in and of itself. Unless we can read the minds of other people there really is no way to prevent isolated attacks, whether they are influenced by a specific group or not. People sometimes snap and there is nothing we can do about it,
I don't think lone wolf attacks can be stopped. Lone wolves by description act independently. This independence can also lead to the acts they commit being random. This randomness will make it difficult for law enforcement to find and follow lone wolves. If law enforcement cannot identify the lone wolves, it will be almost impossible to stop them.
"Lone wolf" attacks are planned out and perpetrated by people who are so messed up in their thinking that they will commit the attack whether someone is there to stop them or not. They do not need the group mentality to get their crime committed. I think a stronger action against all attacks may bring some questions to the lone wolves but nothing will ever change their minds or actions completely.
Lone wolf attacks are virtually impossible to stop. Although law enforcement may be able to get a tip to stop isolated lone wolf attacks, in which an individual launches an attack based on inspiration from a terror organization rather than outright support, it cannot stop the majority. There is limited intelligence tools that can be used since it is an individual that can use common items, such as the British woman stabbed to death at an Australian hostel.