Germany's Constitutional Court ruled on Oct. 12 that Bonn can sign the Maastricht Treaty for closer European political and monetary union. But the decision was far from a big victory for backers of European unity. True, the last holdout among the European Community's 12 members is now in the Maastricht fold. But the court in effect said that such controversial issues as giving up the German mark for a Eurocurrency would have to be put before Parliament--which might well reject them. It also reserved the right to intervene if Brussels bureaucrats overstep their bounds.