I agree that it's probably not 5D chess. But I have to contest that speed is to their advantage given such asymmetric military strength. A slow bleed prolongs the process while the world looks on and energy prices steadily rise. They certainly aren't endearing themselves with their neighbors but at the same time by only striking a minimum amount of infrastructure they avoid mobilizing the sentiment of the broader US or EU populations against them.

My impression is that an overly intense or otherwise disproportionate attack would risk inviting a significant increase in political support. Whereas so far it seems to be a wildly unpopular military campaign.

IMO the US botched this quite badly. I'm almost certain we could have found a way to go about disposing of someone who guns down protesters en masse and funds terrorism without inviting so much negative sentiment or economic volatility.