Why Spain's decline was not inevitable

Was Spain's decline inevitable by the time of the Spanish-American War?

No; decline is not automatic, but it becomes entrenched when governments repeatedly fail to correct damaging institutional and strategic decisions.

Spain's decline resulted from choices that could have been changed. Repeating damaging decisions allows weakness to persist, but it does not make the outcome inevitable. Fleet-reform exercises likewise draw attention to organization and dispositions where much of the available technology is already being adopted. Institutions can still change how they arrange and use their forces.