In 1962... we asked Pakistan to join us in the attack against India.
But Ayub Khan preferred to side with India, for his own reasons. He had already offered a joint-defence pact to India three years earlier in 1959 during the Sino-Indian border clashes that year:
Bhutto`s foreign policy legacy - DAWN.COM
I would argue that if Pakistan had joined us in 1962, all of Kashmir would currently be in Pakistan's possession.
And we would probably have had a mutual defence pact, similar to the one between China and North Korea that saw massive Chinese military intervention during the Korean War, leading to America's longest ever retreat in history.
Such a mutual defence pact could have also prevented the loss of East Pakistan.
As it stands today, there is no mutual defence pact between China and Pakistan. I would argue that Ayub Khan's decision to side with India instead of China was a massive lost opportunity for Pakistan, and that should this opportunity arise again in the future, the other path would have been a better choice.