How are they fighting the "wrong battle" when complying would be a breach of Irish law? If the US DOJ is so keen on this data, they should get the Irish law enforcement in the loop.

So because the accused are in the middle of a drug case, that makes this okay?

No it makes it OK because everything is in the open.

When you're in a middle of a drug case it's pretty normal that they read your emails.

It's not normal that they read secretly my emails when they have nothing against me.