ECB's Liikanen says the ECB can hold rates even after summer 2019 if needed

Spain, Italy and greece will crack up if they rise rates.

Sure they can keep interest rates low, assuming there is no real economic downturn or crisis that hits, because when it does, they are out of instruments to kickstart the economy and crisis will take even longer as it did now..

Maintenance of stimulus recklessly, whether in US EU Japan ..wherever... and dangers of the limitations that lack of early normalisation creates for capacity to react to future downturns a perennial debate. Give current challenges my personal view is that ECB is doing well. Naturally others may differ.