Is it necessary to establish a khalifa?
This is not only a problem with Pakistan, people in Bangladesh are willing to kill someone or even die for their political party. Same with other places which I won't mention. If only people realised that having this western style of democracy won't bring peace.
If people could spent their time/effort and were willing to die for Allah (swt) cause. Which is to re-establish a Khalifah and live under rules which Allah (swt) has prescribed.