They are weekly marches found to be organised by organisations with links to Hamas, and at least one ex Hamas member.
They are supporting a terrorist organisation that has just committed the deadliest day in Israel’s history. An Iranian dissident was arrested for holding a sign saying Hamas is Terrorist, despite the fact that they are a UK-designated terrorist organisation - because protestors assaulted him on seeing the sign.
If they were calling for peace and fewer casualties they would be condemning Hamas and calling for them to surrender.
AIBU to think this is deeply disturbing and has no place on the streets of London. Note - terrorist support is illegal and not protected speech.