What is the difference between striving against the self (jihad al-nafs) and striving against desires (jihad al-hawa)?

It appears that the meaning of struggling against the self (nafs) and struggling against desires (hawa) is either unified or that each necessitates the other. Struggling against the self is more general, as it includes compelling the self to perform acts of obedience and avoid prohibitions, whereas struggling against desires is more specific, referring to opposing the desires of the self—that is, unlawful cravings—making it a part of struggling against the self. Thus, every opposition to desire is a form of struggle against the self, but not every struggle against the self involves opposing desire. The one who struggles (al-mujahid) is he who subjugates his self, which inclines to evil, to that which pleases Allah, by performing acts of obedience and avoiding disobedience.