Midway was important not just in terms of the Pacific war but the entire world war as well. A Japanese victory would have made it very difficult for the U.S. to contribute much in Europe for some time.
I'm not so sure that the European support had not already taken place and the Pacific war was the one less supported from the beginning. The first two to three years we were fighting on our terms, bypassing the large islands and choosing our battles very carefully to husband the limited resources we had in the pacific.
I think the Battle of Okinawa in 1945 marked the first full scale invasion against a very large Japanese force and the full brunt of the Kamikaze pilots. By April 1945 the Euorpean war appeared to be won, and so it was time to step up the pressure in the Pacific.
Fortunately, or unfortunately, the huge losses we and the japanese experienced at Okinawa probably figured into the decision to use the BOMB, instead of invading Japan proper. According to an article read, the losses were so great, over 12,000 US dead, and 38,000 US wounded, they sparked congressional crys for investigations.