The F-35 that Australia is likely to purchase is having a difficult birth - no surprises here, as no fighter program in modern history has come in on time, on spec or on budget. But that aside, questions are being asked as to the F-35's suitability to Australian's defense requirements. The aircraft may simply be too small to meet all of Australia's needs, with big question marks remaining as to its ability to counter the advanced Su-27 derivatives which are now proliferating in Australia's region.