MQM is a cancer, and thank God, all the political parties are covertly working to keep this Cancer to Karachi. All that has been discussed above about the inhuman attitude of MQM, and its workers (butchers), target killing in karachi etc etc are true, and everyone condemns it. But, the attitude of the political parties is so selfish that actually makes MQM survive. All the political parties know well what MQM is, and whats its agenda. They just want (so far) "Don't look at Karachi, its ours". Where army operation will help eliminate the butchers, there are fears that MQM might reap its hidden benefits and will manage to win the sympathies of the people (in that every time, they are made escape goat, they are slain etc etc).
On the other hand, Govt won't take this risk because it has no confidence on other parites; other parties especially 2nd largest party PMLN will espouse the operation, but at the same time, will keep waiting for a moment to kick the govt out (mis)utilizing the time of operation. Moreover, the govt will do its best to keep its side strong (with PMLQ, MQM, ANP etc). It will ensure its survival in every state whether it has to knock the door of any party. However, "N" is main rival, so it will depend on others. To ensure its survival and to keep the army coup away, the govt is constrained to surrender to MQM, its just so because other parites for their ulteior motives are not realizing what destruction MQM may cause, and their selfish attitude towards the govt (every govt) is causing the expansino of MQM.

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