This is simply not true. Most regional traditions of Buddhism do not allow for the use of violence with justification and, regardless, the Buddhist suttas do not provide any such justification.
1. The teaching itself
2. The clerical institution, often fused with and distorted by state power
3. The practice as understood and lived by ordinary people
1 always remains "highbrow" and isolated from the stresses of 2 and 3; and it's 2 and 3 that set the tone of a religion.
The problem of the discussion here is that some participants are claiming that Buddhism is not anti-violence which is like going around claiming that Christianity/Islam is not anti-polytheism.