In this Letter, analytical arguments are presented for the existence of a synchrotron X-ray jet on large scales in most radio-loud active galactic nuclei, based on the knowledge of the nature and physics of blazars. In blue blazars and blue blazar-like radio galaxies, the large-scale X-ray jet may become faint along the jet, while in most red blazars and red blazar-like radio galaxies, the X-ray jet is bright on 10 kpc scales whether the jet is highly relativistic on large scales or not. In extreme red blazars in which the jet is still highly relativistic on large scales and the synchrotron peak of the inner jet lies in the infrared bands, the X-ray jet may become fainter along the jet from 10 to 100 kpc scales, while the optical and IR jet becomes brighter. The predictions can be tested with the ongoing observations of the Chandra X-Ray Observatory.