>Effective
The problem with political violence is that the other side will do the same thing, and you end up with an IRA situation where the country descends into sectarian violence.
The problem with refraining from political violence where it is warranted is that the other side will do it anyway and you end up dead.
The IRA situation had a slightly lower bodycount than the not-throwing-1930s-fascists-into-the-sea one, did it not?