Why Ireland didn't qualify for the World Cup

Out of the norm I have to comment on a football match I have just seen. Actually, it wasn't a match. It was a near massacre. The Republic of Ireland have some guys who can play above average. Brazil have some guys who play average, the rest are well above. We have a manager with a great reputation, but someone who is aging, shown himself to be beligerent and one dimensional.
We have a team that cannot match the top flight of international football. I understand 2 central defenders were missing but there is no excuse for a having a midfield where Brazilians can waltz from one end of the field to the other, flicking, backheeling, nutmeging and in truth making fools of footballers who are paid astronomical sums of money in a league that promotes itself as the best in the world.
One of the guys playing tonight for Ireland was responsible for the goal scored by the French Hand in Paris in November last. He was at his usual game again tonight, not covering, letting defenders get between him and the goal, unable to keep the ball and has no business in a professional soccer outfit never mind wearing the green jersey of Ireland.
Frankly I was aghast at the gap in quality, style, and effort. I had high hopes after Paris that Ireland would go on and build. They have slipped dangerously backwards to  Stautonesque proportions. I am just glad it wasn't 6 or 7 because it could have been.