Operation FS was postponed following the Japanese setback at the Battle of the Coral Sea, then cancelled after the Japanese defeat at the Battle of Midway, following the losses of four Japanese fleet carriers. The land forces originally dedicated for Operation FS, namely the 17th Army, were instead reassigned to a subsequently unsuccessful reattempt to take Port Moresby, part of the original goal for Operation MO, and to defend the Solomon Islands from Allied offensives.