there were IRA snipers in the vicinity - now admitted to be a lie.

Now known to be true. See above.

I believe you've even put forward similar excuses for the massacre yourself (another lie, no doubt).

No, I have never claimed it was self defence.
Who here ever has?

The deliberate targeting of civilians by Israeli troops has bacome commonplace

I am not aware of this, please substantiate.

The deliberate targeting of civilians by Palestinian fighters has been a commonplace for years.
Do you need that substantiated?