All through our studies on the life of Imam Hasan [a], whether during the lifetime of his father or during his own reign, we witnessed his strength of character, his steely determination, and swift action to sort out problems and reach sound, logical solutions. This was something which was matchless. We witnessed all this and lived it, in the light of historical documents which cannot be doubted. We witnessed it in his stirring of the zeal of the people of Kufa to defend Islam in the battle of al-Jamal.
We saw him urging the people to fight against Mu'awiyah in the battle of Siffin. We saw him addressing the camp of his father after the arbitration. When he assumed the office of Imamate, we saw him, as he had been during his father's reign, possessed of determination, resolution, cleverness and skill. He took urgent measures to solidify the foundation of his state. He persisted in challenging the Umayyad falsehoods, and putting down the seditions of Syria, to stabilize the Islamic state.
He faced all the attempts of Mu'awiyah to corner him, before the start of the war, with a lofty, sublime spirit, the spirit which knew nothing but the right and would never lower his head before the forces of falsehood. The prevailing conditions at the time, however, kept him at bay, something which has rarely taken place throughout history.
The army led by Imam Hasan [a] became the prey of disorder. Spies, agents and the bearers of disrupting news found their way into it. Imam Hasan [a] was on the brink of being forced to surrender to his enemy! The ummah, which he was planning a bright and successful future for, and leading its march into history, diverted its course to the advantage of his foe! That was the result of the rumours and luring promises.
These factors caused the tip of balance of power to tilt on behalf of the Umayyad interests.
Following are the most important of the painful events which were inflicted on Imam Hasan [a] as a result of his stand in the face of the incursion or the treacherous Umayyads:
Next to these people, there was a group who were loyal to Ahlul Bayt [a]. They were a small number in comparison to the increasing number of the rag-tag, and the intensity of the hostile schemers.
Money was a doubled-edged sword. In addition to its sharp effect in changing the balance of power to the interest of Mu'awiyah, it left its most surprising imprints in the hearts of the Iraqis. They flooded Mu'awiyah with their letters declaring their loyalty and obedience to him. They promised to hand Imam Hasan [a] over to him as a prisoner when the fire of war blazed and zero-hour came!
Imam Hasan [a] referred to this treachery when he said:
"By Allah, if I had fought Mu'awiyah, they would have taken hold of my neck and handed me peacefully over to him. By Allah, making peace with him with nobility, is more loveable to me than being killed by him as a captive, or set free, which would be a stain for the tribe of Hashim." 
Following are some of the statements of the Imam which display his noble intentions:
"I feared lest the Muslims should be uprooted from the surface of the earth. I wanted the faith to have men who call to it."
"...I only wanted, by my treaty with Mu'awiyah, to spare you death."
This soul, attached to Allah, the Most High, and inspired by Him and His noble shar'iah, made Imam Hasan [a], wherever he was, to keep away from entering into a war in which blood would be unnecessarily shed, and men killed without result. In addition to that, the factors in Islam's view, were not in the least available, as we have witnessed by the character of his unprincipled followers.
This is quite different from Mu'awiyah who would never care how many men were killed, and how much blood was shed, as long as he remained the ruler of the Muslims, to whom the income of taxes were brought. He was the ruler who basked in mundane luxury and fleeting pleasures in the palace of alKhadara'.
Those who obeyed Mu'awiyah would bear the responsibility for that historical tragedy in which the ummah lost the leadership of Ahlul Bayt [a] and their pioneering Imamate, not only during their blessed existence, but also after their deaths. The negative impact of that continued smashing the ummah, generation after generation, till the system of Islam, which was expected to prevail and rule, was reduced to a mere historical heritage buried in the books.
The second attempt on the life of Imam Hasan [a] took place when a man jabbed him with a dagger while he was in prayer. Again the Imam [a] was unhurt.
In the third assassination attempt he narrowly escaped death. A mob attacked him, plundering his tent and taking his prayer-rug from under his feet! During the attack al-Jarrah bin Sinan al-Asadi stabbed him with a rapier in his thigh and gravely wounded him.  The blade reached the bone.
After that attempt, the Imam was bed-ridden and remained as a guest at the house of Sa'd bin Masood al-Thaqafi, his governer on al-Mada'in.
The mobs were angered beyond limits and attacked his tent. They condemned the alleged peace, but at the same time they were too indolent to fight.
By clarifying all these sides, Imam Hasan [a] paved the ground actually for the revolution of the Lord of Martyrs, Imam Husayn bin Ali [a].
These are, our dear readers, the most important justifications and causes which prompted Imam Hasan [a] to sign the document of treaty with the treacherous Mu'awiyah.
Would any other ruler or leader, if faced with what Imam Hasan [a] faced, take another course of action?
War, after all, would have been an impossible option. No sane man would have adopted it. Then how could a great man like Imam Hasan bin Ali [a], do it?
Some people would be of the opinion that it was better for Imam Hasan [a], if he had sacrificed all for the sake of his right. If, however, Imam Hasan [a] had fought, he would have surely been killed, along with all of his family. The Umayyads would have succeeded in extinguishing the light of Islam for good. No one could then tell the right from the falsehood. The ummah, would never have realized, as it did afterwards, how deviated were its rulers, and what bondage they were led to.
Imam Hasan's [a] concern for Islam made him sign the document to play his role, afterwards, in explaining the Shari'ah, its laws and dimensions to the ummah of Muhammad [s], during his remaining years, as we will see in this phase of his life.
We deem it suitable to cite the most important items of the document signed by Imam Hasan [a] and Mu'awiyah: 
These are the items of importance of the treaty which were accepted by the two parties. As it is clear for the reader, it is of great benefit to the ummah and its noble Message. These terms were the most that Imam Hasan [a] could achieve for the ummah and its mission. If any better could be achieved, he would not have hesitated to take advantage of them.
A number of Muslims objected to the treaty. Imam Hasan [a] explained to them why he had taken this step. He said to Bashir al-Hamadani:
"I am, by no means, humiliating the faithful, but honouring them. By my making peace, I only wanted to spare you death, when I saw my followers lingering and refraining from going to war."
Al-Hamadani was the first one who was too cowardly to fight.
To Malik bin Dhumrah, who talked to him about the document, he said:
"I feared, lest the Muslims should be uprooted from the surface of earth. I wanted the faith to have men who call to it."
He said to Abu-Sa'eed:
"Abu-Sa'eed! The reason why I made peace with Mu'awiyah is the same one which made the Messenger of Allah [s] make peace with the tribe of Banu Dhumrah and Banu-Ashja', and the people of Mecca when he returned from al-Hudaibiyyah."
Imam Muhammad al-Baqir [a] refers to the significance of the treaty, and its positive effects for the benefit of Islam and Muslims, in these words:
"By Allah, what Hasan bin Ali [a] did was better for this ummah than what the sun had shone on." 
 Shaikh al-Mufid, Al-Irshad (The Guidance), p.208, and al-Fusool al-Muhimmah, p.146
 Muhammad Jawad Fadhlullah, Sulh al-Imam Hasan, p.76.
 Al-Irshad, Life of Imam Hasan [a], p.209, and the following pages.
 Tawfeeq Abu Alam, Ahlul Bayt, p.335.
 Hayat al-Imam Hasan [a], 3rd ed., vol, 2. pp.103-105.
 Bin Abi al-Hadeed, in his commentaries on Nahj al-Balaghah, says that it is "ma'wal" (pickaxe) and not "maghwal" (rapier), see vol.16. p. 41.
 Al-Irshad, Life of Imam Hasan [a], p.209.
 For details see: Al-Fusool al-Muhimmah by Ibn al-Sabbagh, and Ahlul Bayt by Abu Alam.
 Statements of Imam Hasan [a] are quoted from Hayat al-Imam Hasan, vol. 2. "Protestors at the Peace Treaty", p. 281.
 Rawdhat al-Kafi (Orchards of al-Kafi), vol. 8, p. 330.