Brussels — For the first time in NATO history, an officer from West Germany has taken charge of the nuclear-weapons portfolio within alliance military command. Officials said that the responsibility had been given to Gen. Hans-Joachim Mack - one of two deputies under Gen. Bernard W. Rogers, supreme allied commander Europe (SACEUR). Previously the job had been held by the SACEUR's British deputy, who is now Gen. Sir Edward Burgess.
Observers cautioned that the transfer of responsibility in no way affects control of nuclear weapons in time of war. ''It has nothing to do with the release of nuclear weapons,'' according to a senior alliance official. ''That decision remains in the hands of the United States.''
But some analysts felt that the transfer was likely to have a significant psychological impact on the Kremlin, which has been waging a so-far unsuccessful battle to ''freeze West Germany out of NATO,'' as one alliance official put it.
The development is the first major change in NATO's military command structure at the top since 1978 when then-SACEUR Alexander Haig created a deputy post reserved for West German officers. Until then, there had been only one deputy SACEUR, a British officer. It is felt the Germans were given the job because they have the largest conventional land forces in Western Europe and because their country, as a ''front-line'' nation, has vital interest in strategic issues.
Since 1982, the British deputy has advised on operational matters, while the West German deputy dealt with maritime affairs and so-called ''support matters.''
General Mack replaced West Germany's Gen. Gunter Kiessling as deputy SACEUR earlier this year following charges that Kiessling had frequented gay bars. Kiessling has firmly denied the charges but his departure was seen as almost inevitable in the wake of wide publicity over the issue.
Mack is close to Rogers, having served as deputy chief of staff for planning and operations under him from 1981 to 1983. In his new job - as in the past - his responsibility will be to monitor developments in his portfolio and to advise the SACEUR. Now he will be concerned with nuclear and conventional defense.