Be it the treaty between Muhammad, son of Abdullah, and Suhayl Ibn Amr the envoy of Makkah or be it the treaty between Hassan, son of Ali and Muawiyya ibn abu Sufyaan the self appointed Amir of Syria, None of the terms of both treaty violate any doctrine or article of Islam.
Yes, that is our [Ahl us-Sunnah] position. However, the Twelver shiites believe that sayyidina Hasan bin Ali رضى الله عنهما was a divinely appointed Imam and hence no one but him had the
right to rule over the Muslim Ummah.
We do not hold to this doctrine, thus the treaty with Mu'awiya رضى الله عنه presents no difficulty for us.
Now according to the treaty, sayyidina Hasan
resigned from the office of ruling the Muslims.
Furthermore, at least according to our narrations (and perhaps yours as well - we can investigate the issue), sayyidina Hasan رضى الله عنه gave the Bay'a to Mu'awiya رضى الله عنه.
Whether you believe he gave the bay'a or not, it is at least agreed that he resigned from his office which you as a Twelver believe he was divinely appointed to.
Now let me ask you, can a divinely appointed Imam resign from something which he has a divine right to?
Neither did Muhammad s.a.w give up His divine authority nor did Hassan give up His divine authority.
Sayyidina Hasan gave up his divine authority to rule over the Muslims.
Muhammad s.a.w and Hassan both acted in the long term benefit of the Muslims.
How is it in the long term benefit to resign from that which God Himself appointed you to?
But the Muslims turned out more ruthless and savage than the Makkan Pagans by butchering the progeny of the Prophet s.a.w in Karbala and taking the rest as prisoners and severely mistreating them.
How is this relevant to our present discussion? Btw those Muslims were Kufan ex-Shiites as we already discussed elsewhere.
Furthermore, you just contradicted yourself, because you said Imam Hasan رضى الله عنه gave up the rule in favor of Umayyads for the
LONG TERM benefit of Muslims. Yet within a decade or thereabouts of having done so the Ahl al-Bayt are massacred by forces loyal to Umayyads. How is that a long term benefit?
Hassan never accepted Muawiya as his ruler or gave allegiance to him. He just stepped aside to stop the innocent blood of Muslims being spilled from both sides over this worldly status of Caliphate.
In your doctrine the "worldly status of Caliphate" is the
divine right of the 12 Imams and no one else!!!
How could Imam Hasan "step aside" from his divine right?