It was a moment described by Tony O’Reilly Jr as a “seminal day for Ireland, especially in the runup to St Patrick’s Day”. It was early March 2012, and Providence Resources had just told the stock market it had hit oil in Barryroe, off the coast of West Cork. “As the Americans say, ‘We didn’t hit a home run, we knocked the ball out of the park,’” O’Reilly Jr enthused. Providence said its results had “far exceeded pre-drill expectations with oil rates in excess of 3,500 barrels of oil per day.” The field was estimated to potentially contain billions of…