i have tried to solve this question though it become too long as it is my first attempt. senior please check it and and sort out mistakes.

Q) The Kashmir problem has been mishandled from the beginning and every successive Government in Pakistan has contributed to that". Critically explain the statement
ANS) It takes two to quarrel. We cannot solely blame Pakistan government to mishandled Kashmir issue. Most probably India has played its bigger role in botching Kashmir issue. Though Pakistan have go through several ups and down in its Kashmir policy from resorting to UN then to bilateral talks, then to supporting jihad in Kashmir and ultimately back to pressurizing un to decide Kashmir issue. But at the same time India drifted from its early stance of self determination to kashmiri to declaring Kashmir as its integral part and internal issue. Hence, shutting Kashmir issue in UN.
Soon after the independence lack of trust between newly emerge states over princely states lead to outbreak of 1948 war. India rush to UN and ultimately a ceasefire was declared by UN on 1 January 1949. a ceasefire between Indian and Pakistani forces leaves India in control of most of the valley, as well as Jammu and Ladakh, while Pakistan gains control of part of Kashmir including what is now Azad Kashmir and Gilgit–Baltistan. According to the terms of cease fire Pakistan have to withdrew its forces from Kashmir while India have to deploy minimum forces to maintain peace and order. Pakistan hesitated to withdraw forces because in this way India could maneuver to annex Kashmir. However Pakistan withdraws forces by complying with the terms of ceasefire but Indian forces continued their suppression on Kashmiri Muslims. According to UN resolution it was decided that a plebiscite will be held in Kashmir to decide the future of Kashmir. Pakistan urged that the plebiscite should be held under the presence of Pakistan forces too in Kashmir otherwise the plebiscite result could not be of credence. Fortunately after some years UN Security Council revised the terms of resolution on the suggestion of General Andrew. According to the new terms it was declared that both the India and Pakistan have to withdraw her forces. All of the terms were accepted by Pakistan but declined by India.
Pakistan police on Kashmir was not coherent from its early. First Pakistan says that it was merely supporting an internal revolt in Kashmir but later on acquiesce that he supported tribal fighters to be sent to Kashmir.
During earlier years India officially declared that she is in favor of granting self determination to people of Kashmir through plebiscite. Indian Prime Minister, Jawaharlal Nehru, in a speech aired on All-India Radio, reaffirmed the Indian Government's commitment to the right of the Kashmiri people to determine their own future through a plebiscite: "We have declared that the fate of Kashmir is ultimately to be decided by the people. That pledge we have given, and the Maharajah has supported it, not only to the people of Jammu and Kashmir, but also to the world. We will not and cannot back out of it. We are prepared when peace and law have been established to have a referendum held under international auspices like the United Nations. We want it to be a fair and just reference to the people and we shall accept their verdict."
During the early 1950s India remain reluctant on the procedure of plebiscite. And the curtain was lifted when India gradually develop Kashmir its state and then its integral part. India held election in Kashmir in 1951 which resulted in sheikh Abdullah victory. It was widely called that election was rigged and India was only in favor of installing puppet government in Kashmir. It proved through latter development when sheikh Abdullah backed from its stance of joining India to proposing self determination of kashmiri people. India government replaced sheikh Abdullah by installing a more friendly provincial government and imprisoned sheikh Abdullah. Later on in 1956 India's Home Minister, Pandit Govind Ballabh Pant, during his visit to Srinagar, declares that the State of Jammu and Kashmir is an integral part of India and there can be no question of a plebiscite to determine its status afresh. India would resist plebiscite efforts from then on.[20] Kashmiri activists continue to insist on the promised self-determination.
Similarly Pakistan signed agreement with china in 1963 over an area of Kashmir. India agitates on this agreement saying that Kashmir is a disputed area.
Nehru also backed from its earlier stance stating that Pakistan joined Western military alliances in a bid to intimidate India. Though Pakistan assure India that military aid received through joining these alliance would not intimidate India but in operation Gibraltar a large number of these weapons were used.
After several sessions and years of hard work the U.N could not find a solution to the problem of Kashmir. The role of U.N on this issue was almost eliminated after the 1965 war, when the Indian and Pakistani governments signed the Tashkent declaration according to which minister level talks were to be held on the Kashmir Issue. Bilateral talks again promoted in shimla agreement 2 July 1972. in which it was decided that both the countries will resolve their differences through bilateral negotiations. So the Kashmir issue was closed in United Nations. It was already foresighted that India will never bring any issue to international arbitration after the Rann of kutch compromise. Prime Minister Mrs. Indira Gandhi said after the Rann of Kutch compromise “This was the last time that India would go for international adjudication.” Pg 176 Pakistan foreign policy by shahid m amin. however these talks also remained unsuccessful due to the difference of opinion.
After signing of Tashkent declaration in 1966 Pakistan supported guerrilla groups in Kashmir increase their activities after the ceasefire. Kashmiri nationalists Amanullah Khan and Maqbool Bhat form another Plebiscite Front with an armed wing called the Jammu and Kashmir National Liberation Front (NLF) in Azad Kashmir, with the objective of freeing Kashmir from Indian occupation
India deployed half of its army in Kashmir and started human rights violation since then it is claimed that India have killed 90000 innocent in Kashmir, BBC says that there are so many graves. 1980s infiltration, 2010: Indian State Human Rights Commission (SHRC) confirms presence of more than 2,000 unidentified bodies in unmarked graves near the Line of Control. Activists say many may be people who disappeared after being arrested by security forces.
During 1980’s a new tale started in Kashmir. After disappointed from united nation Kashmir’s inhabitant resort to violent means, they were helped by jihadis from Pakistan. Jihadi forces used guerilla warfare to liberate Kashmir. India blamed Pakistan that instability in Kashmir is caused by infiltration from Pakistan. But a struggle so long cannot be continued only with external support, kashmiri themselves are against the Indian suppression. India increased its troops in Kashmir and they started ruthless suppression of liberation movement. They butchered many Muslim, women, child and young men. Human right organizations draw world’s attention to Kashmir sorrow. Human right organization alleged that Indian forces have murdered hundreds of thousands innocent kashmiris and tortured them. When the UN tried to assess the situation of Kashmir in 1990 India refuses to allow any United Nations official to visit Kashmir.
Though Pakistan kept supporting jihadist in Kashmir but at the same time it did not refrain from talks.
On 21 February 1999, India and Pakistan sign Lahore Declaration, agreeing to 'intensify their efforts to resolve all issues, including the issue of Jammu and Kashmir.' It was said that Vajpayee assured Nawaz Sharif on reaching agreement on Kashmir. Both sides showed flexibility in their stance. But as Soon as he went back he faced pressure from hardliners and he too backed from his stance. (Victoria Schofield, Kashmir in Conflict)
In 1999 tension escalated between India and Pakistan over Kargil crises. At first Pakistan military was in positive position. Pakistan ex president general Musharraf says that Pakistan could grab favorable terms in ceasefire by even reaching an agreement on Kashmir if the then prime minister Nawaz Sharif would not have declared unilateral ceasefire. Musharraf justified the policy as a logical response to India’s unwillingness to “discuss Kashmir at the UN and to resolve the dispute in a peaceful manner.”
Since the Mumbai terrorist attack (November 2008) India has reduced the India-Pakistan relations to a single-issue relationship. That is, Pakistan must satisfy India on the terrorism issue before taking up the resolution of other issues. Whereas India, supported by the United States, blamed Pakistan based militant groups for the Mumbai incident and violence in Kashmir, Pakistan shied away from addressing this question. Furthermore freedom struggle in Kashmir was tagged as terrorism.
During Musharraf era Pakistan has seriously showed flexibility in its policy to reach agreement on Kashmir issue. Chenab formula was also revised and proposed to India but India focused on other issue to be discussed first. Pakistan reverted to its previous policy that Kashmir is the jugular vein of Pakistan and no talks which exclude Kashmir issue. Similarly now India stuck to its stance that terrorism should be discussed before discussing Kashmir. Furthermore she takes Kashmir as its internal matter. It can be viewed when in 2014 Pakistan's High Commissioner in Delhi consulted Kashmiri separatist leaders in advance of the talks and India cancels talks with Pakistan after accusing it of interfering in India's internal affairs.
Pakistan have moved from its earlier policy of losing hope in UN and then to bilateral discussion which also could not brought any result. And Pakistan moved to supporting jihad in Kashmir but the 9/11 shut its jihad too labeling it terrorism. At the same time Pakistan could not be blamed for all this India too have moved from its stance of self determination to declaring Kashmir as its internal issue. Hence both nations require adopting flexibility in their stance to reach a feasible agreement on Kashmir issue.

i haven't studied your whole topic but read some paragraphs, your writing seems incoherent, and lacked in proper grammatical usage.
like:
newly emerge state, in-spite of newly emerged state;
analysis looks pretty good if stretched through its roots;

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