Ask HN: Is it possible to create counter-terrorist consensus on blockchain?

So let's say we have a set of wallets which are used to support terrorist organizations. Can we write a patched BTC/ETH clients/miners to freeze those wallets? This way we can perform >50% counter attack on terrorists?

I am not blockchain expert, sorry if this sounds stupid.

I am asking this because I can't stay rest seeing Ukrainian civilians being killed by bombarding residential areas.