It is a great point.I have no doubt you are sincere when you state that you'd march against the terror attacks committed in Bondi, Manchester, London, Manhattan and Sweden.
but of course you won't, because there won't be any, at least not one you'd be comfortable attending.
I wouldn't march with the far-right, no.
It is a shame that such a march would likely be anti-Muslim rather than pro-life, or anti-terror. If it was either of those, I absolutely would, and I think there is a strong case for such protest.