These days ''playing the China card'' is something that almost any politician can do. But playing the China card can be a bit like playing with a boomerang. It sometimes comes back to clip you.
Indeed, what began with President Nixon's opening to Peking has become the province even of that special species, the big city American mayor.
Take Boston's Kevin White. This redoubtable, craggy-faced 15-year City Hall veteran took an entourage of officials on a late April visit to Peking. Then it was on to Boston's beautiful sister city, Hangchow. The month-long tour brought the four-term mayor more than a few brickbats from skeptical Bostonians who thought his outlook should be a bit more local. But that was not the end of it.
It also brought him some hopes of tying tighter the links of commerce between Boston and the People's Republic of China. Symbolically important, it raised a foreign policy question for the city of Paul Revere: Can Boston, and indeed other cities, have a ''two Chinas policy?''
The answer appears to be ''yes.''
The proof came late last month when an eight-man delegation of Republic of China mayors from Taiwan made a whirlwind tour of US cities.
If Boston-born, -bred, -schooled, and -elected Kevin White could leave his city long enough to visit the communist People's Republic of China, it seemed hardly surprising that Peking's Nationalist competitor seemed willing to go all the way in an effort to ''show the flag'' in the United States.
''Learning requires reading 10,000 books and traveling 10,000 miles,'' Taipei's earnest ''technocrat'' Mayor Jackson C. T. Yang told a Boston news conference.
Mr. Yang, a respected Taiwan-born engineer who jokingly labels himself ''M.I.T.'' (''Made in Taiwan''), seemed happiest and most impressive when discussing his impressions of Boston's urban renewal, the city's underground parking, and the future of trade and cooperation between ''high technology'' New England and an increasingly technology-oriented Taiwan.
Mayor Yang seemed visibly uncomfortable with the swirl of international politics that seemed to follow him nearly everyplace. Under questioning by journalists, he and the other mayors generally uneasily demurred to the crib notes, whispered promptings, and direct interventions of the accompanying diplomats who staff Taiwan's equivalent of a consulate, the New York-based Coordination Council for North American Affairs.
At home, politics might be their life. But these mayors needed plenty of help when placed in the position of international politicians.
Judging from the questions, the local press had little doubt just why the mayors had come. Their visits to Boston, Detroit, Dallas, Los Angeles, as well as Minneapolis (where they visited the US Conference of Mayors) seemed designed to show Taiwan ''homefolks'' that despite ''normalization,'' the men from the Republic of China are still welcome in the US.
So for some the ''$64 question'' was whether Kevin White's economic eyes - perhaps fixed on Peking - would flicker even briefly in recognition of Taiwan.
As it turned out, that was no question at all.
The mayor met the delegation long enough to receive an invitation to visit Taiwan. Although White's spokesman, George T. Regan, said the mayor was ''flattered'' by the invitation, he said there were no plans in the near future for such a trip.
''Mayor White's response was appropriately warm,'' declared one Republic of China diplomat.
For experienced Boston ''pols'' like former City Councilman James Michael Connolly, Kevin White's soft spot for Taiwan was hardly surprising.
''Boston politics is local,'' said Mr. Connolly, now a registrar of probate for the Suffolk County Court, who declares he plans to run to replace Mayor White in 1983.
''Mayor White simply has a lot more voting constituents from Taiwan than from mainland China,'' the mayoral hopeful declared just before a luncheon appointment with Taipei's Mayor Yang.