ISLAMABAD, Pakistan — As relations with Washington plummeted in the aftermath of the killing of Osama bin Laden in May, Pakistan’s leaders turned to China, which is seen here as an enduring all-weather friend, an alternative to the troublesome and overbearing Americans.

Over the years, Beijing has sent military assistance to Pakistan, provided crucial help in initiating Pakistan’s nuclear weapons program and cooperated closely on intelligence. Sturdy Chinese-Pakistan relations are seen as a hedge against India, a rival to both nations. In recent months Pakistani officials have gone to Beijing seeking Chinese investment in a naval base and weapons, as well as trade deals worth millions of dollars.

But on closer examination, Pakistan’s ability to use China to offset its collapsing relations with the United States may be far more limited than it appears, raising the prospect that Pakistan will be left on the world’s periphery once the Americans wind down the war in Afghanistan and vastly reduce their presence in the region.

A rising China with global ambitions is unlikely to supplant the United States in Pakistan, according to Chinese experts on Pakistan, as well as Pakistani and American officials. And while Pakistan’s latest flirtations with Beijing have been received cordially, Pakistani officials have walked away from their junkets with far less in hand than they might have hoped.