American Vice-President George Bush's tour to West Europe next month comes none too soon. Strains in American-European ties are again appearing on the horizon.
The latest warning of developing transatlantic friction came in a confidential West German communication to the Reagan administration at the turn of the year. The warning from America's linchpin European ally was especially noteworthy since it comes from a conservative government that came to power three months ago on a wave of effusive pro-American and pro-Reagan rhetoric.
As described by West German and American diplomats and officials, the potential issues once again tend to pit Western European governments and the US State Department against the US Defense Department - with final policy decisions in each case left up to an unpredictable White House and National Security Council.
The hottest issues (with the exception of agricultural protectionism) are shifting back from 1982's economic to this year's military disputes. This is partly because of the State Department's provisional success in ''damage limitation'' in economic quarrels, partly because 1983 will be ''the year of the missile'' in Europe. The issues include especially:
* Euromissile arms-control negotiations.
* American protectionism in weapons purchases and sales.
* East-West trade.
* Other, recession-generated economic frictions.
Arms control: This is potentially the most exlosive transatlantic issue. Initial NATO deployments of new missiles are due at the end of 1983 in West Germany, Britain, and Italy - if there is no prior East-West agreement on Euromissile limitations.
In brief, in order for deployment to be politically feasible in both West Germany and Britain - where conservative governments staunchly support the stationing but face formidable grass-roots antinuclear movements - the US must be seen to be negotiating seriously. The arms-control talks must be seen to have failed so far -and failed because of Soviet, and not American, intransigence - or else European public opinion will not support the new NATO deployments.
This point seems to be well understood by the Soviet Union, which is currently launching one peace proposal after another. It is not well understood by the Reagan administration, which is publicly refusing to budge from its opening Euromissile arms-control offer of a year ago. And Washington is in any case burdened with an anti-arms-control image in Europe because of its rejection of SALT II and casual Reagan administration talk in the past about nuclear war in Europe.
A subordinate issue here is the West's public-relations response to the latest Warsaw Pact offer of an East-West nonaggression pact. Western European governments, with Britain in the lead, would like to see a less dismissive reaction from the West than Washington has given.
For Europeans the prime test of American reasonableness at this point, however, will be Washington's willingness to move away from its current maximal position when the American-Soviet Euromissile negotiations reconvene in Geneva in early February. Hence the British, French, and now also West German hints that they would welcome greater American flexibility in the US arms-control position - and the discreet engagement of these governments in Washington's bureaucratic infighting about this position over the next three weeks.
In this battle the Europeans fully back the State Department analysis that a US failure to show flexibility in the talks would be catastrophic. They regret the Defense Department insistence that the only deal that could prevent all 572 planned NATO deployments would be destruction of all 333 already-deployed Soviet SS-20 missiles. In a testy acknowledgment of European nudgings last month Defense Secretary Caspar Weinberger publicly told the Europeans not to meddle in an arms-control decision that is America's prerogative.
But Europeans see arms control as very much their business, too, since the missiles in question would be stationed on their soil. In a democracy this requires public acceptance. And in a West Germany with a population one-quarter the size of the US population compressed into a territory equal to Oregon's and already playing host to 4,000 of America's 6,000 total European nuclear warheads , this is the approximate equivalent of asking New York, Philadelphia, and Washington voters to host the MX in their crowded triangle.
It is hardly surprising, then, that ordinary West German voters (and not just radicals) are concerned about deployments. Confirmation of public misgivings leaked out this month with the results of an opinion poll commissioned by the previous center-left government last September and buried by the new center-right government. In that poll 58 percent opposed new missile deployments if the US doesn't negotiate seriously; 54 percent of conservative voters shared this view.
Under these circumstances the government of Chancellor Helmut Kohl apparently decided at year's end to alert the Reagan administration to potential strains in bilateral relations on arms-control and other issues. It is understood a communication was sent via Foreign Minister Hans-Dietrich Genscher to Secretary of State George Shultz, Defense Secretary Weinberger, and national security adviser William P. Clark. According to a source familiar with it, however, the content of the communication was actually decided by Mr. Kohl himself and the defense minister.
Mr. Genscher - the most senior foreign minister in the Western alliance and chairman of the small Liberal Party that may not survive the March election here - is apparently being used as a stalking horse by the Kohl government in an effort not to disturb the warm personal relationship that President Reagan and Dr. Kohl cultivated when Kohl visited Washington last November. At home Genscher is also serving in this capacity in being the only West German Cabinet member to join the British foreign and defense secretaries, French President, and NATO secretary general in publicly presaging greater Western flexibility at the American-Soviet INF talks.
The West German government's sensitivity about Euromissile issues at this point is only partially induced by the imminence of national elections. The March 6 vote may come up too early (and may be too overshadowed by the issue of unemployment) for antimissile ballots to be decisive; the main peace movement demonstrations will not begin until Easter.
In any case, the conservative government is pledged to implement NATO's planned deployments without - unlike the opposition Social Democrats - reserving to itself the right to decide next fall whether or not Washington has in fact negotiated seriously. The government's long-term concern, however, is the potential growth in anti-alliance and anti-American feeling among West Germans if Washington is perceived as not having tried hard for arms control.
American weapons protectionism: This issue has been a recurring one here, as succeeding American administrations have worked out agreements with allies for a ''two-way street'' in arms sales, only to have the American purchases vetoed at the last minute by Congress and powerful special-interest lobbies. Now the issue has flared up again because of the congressional rider in the December budget bill refusing agreed American funding for weapons containing certain speciality metals. This scotched some West German sales to the US agreed on last year in the course of complex negotiations for increased West German financing for ''host-nation support'' (the program under which additional American troops would be flown to West Germany in an emergency).
In response, Bonn has talked of freezing its own weapons orders in the US. And several members of the Bundestag (the lower house of Parliament) are urging West Germany to abandon ''host-nation support'' altogether, since that deal was in any case more lucrative for Washington than for Bonn.
If that agreement on the host-nation support does collapse, this would decrease both the overall European monetary contribution to NATO and American capability to bring emergency reinforcements to Europe to prepositioned equipment and housing. The special metals clause, if it remains in force, would also stymie comparative-advantage cost cutting within the alliance that alone could make a more credible NATO conventional defense feasible.
All of these outcomes would seriously embitter American-European relations. And Dr. Worner has not been shy about saying so.
East-West trade: This issue is dormant at the moment, thanks to the recent lifting of American sanctions on European firms that are selling equipment for the new Siberian-Western European gas pipeline. The Europeans, for their part, have no intention of reviving the issue.
Nor are Soviet actions likely to resuscitate the issue. The Soviet Union is too bogged down in Afghanistan - and Poland is too subdued in the short run and too volatile in the long run - for the Kremlin to be tempted to exploit new targets of military opportunity in the near future. If no new Soviet adventures set off American embargoes, there will be no cause for fresh US-European strife.
There remains some risk, however, that Washington itself might revive this acrimonious issue. The pipeline truce was provisional, pending various allied studies of East-West trade. And diplomats may find it hard to reconcile the European interpretation of the studies (a face-saving way for Reagan to lift sanctions) with the American interpretation (a more effective means for limiting East-West trade). Already hard-liners in the Reagan administration are seeking to restore effective sanctions in the form of ''national export controls.''
Other economic frictions: The worst clash here is likely to arise over heavily subsidized European Community agricultural exports that - despite earlier EC pledges - are cutting into traditional American export markets. In a stopgap solution another joint study has been commissioned.
In today's prolonged world recession there are strong national pressures for protectionism, however, and little margin for maneuver. In a year in which American farm income has fallen to its lowest real level since the 1930s, a dairy trade war is not ruled out.
Europe's economic gripes about the US include fluctuating dollar exchange rates and the (still) high American interest rates that brake economic recovery in allied countries. The recent limited drop in American interest rates has helped ease the situation somewhat, however. In addition, Treasury Secretary Donald Regan's new concern about the impact of American domestic decisions on the world economy suggests that these differences can be worked out.
NATO: Surprisingly, there are few American-European clashes here beyond the contests over arms control and ''two-way streets'' in arms sales. As its most concrete gesture of solidarity with the US, the new conservative West German government quickly gave Washington a promissory note for $150 million for future NATO ''infrastructure'' spending - thus ending the embarrassing shouting matches at NATO meetings between Defense Secretary Weinberger and ex-Defense Minister Apel.
Cumulative issues: Overshadowing all of the separate issues is the danger that they could work together to produce an emotional critical mass that would make case-by-case ''damage limitation'' of transatlantic disputes impossible.
That is, in America, Europe could all too easly become the scapegoat for the entire drop in Iowa farmers' income, while the recurring suspicions that (even a conservative) West Germany might be soft on the Russians could revive all the old NATO polemics.
In Europe, a perception that the US was ramming new missiles down West German and British throats after sham arms-control talks could foster virulent anti-Americanism.