Mr. Baker's Trip

THE pace of change in shaping a new Europe is quickening. So is the role the US will play in the process. This week will be a busy one in Europe - especially for US Secretary of State James Baker. His trip comes on the heels of last Saturday's summit in Dublin of European Community leaders, who agreed, in effect, to work rapidly toward political integration after the unification of Germany. Mr. Baker's first stop will be Brussels, for talks with officials of NATO and groups within the EC.

On Saturday Baker will travel to Bonn to meet with the foreign ministers of the Soviet Union, France, Britain, and Germany. The subject is the shape of security in the new Europe, and how it will take place once East and West Germany become one.

Among the issues to be discussed: Will NATO continue to have the leading role in security arrangements? Or will the security architecture shift to a new 35-nation pan-European alliance? Or even will the EC, until now mainly an economic union, begin to wade in more heavily, as Bonn and Paris have suggested? What about the placement of nuclear weapons? Should Germany be allowed its own arsenal?

These meetings are significant because, for the first time, all the important European questions are on the table: German reunification, economic union, politics, security, sovereignty.

Few major decisions are expected out of the sessions in Brussels or Bonn. But they are crucial in establishing a process for the harmonizing of a freer Europe - a process that will continue for several years in resolving such issues as:

How are the Eastern European states to be integrated? Hungary wants to be an EC member by 1995. Poland and Czechoslovakia have similar desires. How will the monetary union of Europe be finalized? Will West Germany pay the entire $600 billion-plus tab for reunification, or will other EC states directly or indirectly chip in? Who pays for Soviet troops in East Germany? What's the timetable for their withdrawal?

Contrary to some sentiments on the continent, the US role in the new Europe may quietly become more, not less, important. Whether or not NATO wanes as an influence, a number of nations will continue to look to the US as a buffer not only in dealings with the Soviet Union, but with a unified Germany as well. The Netherlands, Norway, Britain, France and others want the US in a security structure. As European-integration issues begin to move past the visionary and into what Margaret Thatcher referred to on Saturday as ``the nitty gritty,'' the US can act as an honest broker for disputes.