You can't replace the F-35 with an F-18 any more than you can replace an aircraft carrier with a cruise ship

An F-18 cannot do everything an F-35 can do, unless stealth doesn't matter. Stealth planes are complex machines. The science of stealth is really two sciences carefully put together: materials and shape, forming an outer casing of an airplane that hides the sensitive guts inside from hostile RADA...

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