Its the 1960s and your Air Force will choose only one fighter for its core, choose!

Its the 1960s and your country will choose one type to make up its fighter core. which would you choose?

some examples of aircraft of this era

US: F-4, F-104, F-5A
UK: EE Lightning
France: Mirage 3
USSR: MiG-21, Yak-28 Firebar