Old salts felt the same boyish delight as President Reagan when he brought one of his country's big World War II battleships back to life in California this week. No less delight is warranted for another launching announced on the same day back in New Jersey, the state for which the battleship happens to be named. It was the first test, and a successful one, of a huge nuclear test reactor on the path toward humanity's use of the kind of fusion energy found in the sun.
Could there be a more striking coincidence for a time of the year full of looking backward and looking forward? A time of trying to choose what to preserve from the past and to pursue in the future.
It should not be surprising that controversy surrounds such choices. The overriding promise in a land of free thought and free government is that the ability to choose is not foreclosed. Freedom provides both the climate for expanding ideas and the political means for acting on them so that in the long run, and in net effect, the best can prevail.
In the case of the new/old battleship, as Mr. Reagan said, its success will lie in its never having to be used. The success of fusion energy, on the other hand, will lie in its being widely used as a safer, inexhaustible alternative to today's nuclear fission power.
The enormous engineering challenges of fusion have pushed expectations of commercial use far in the future, even after the most effective method is determined. Recent projections of energy for a half century from now do not include any role for fusion.
Yet should fusion be delayed more and more through cutting back on funding for research? The Reagan administration has asked for less federal money than in the past, even as some other countries are increasing their fusion expenditures. Here is where Congress can play its part in free government to ascertain if more investment is needed for responsible protection of the public interest.
On the matter of recycling the past, President Reagan now has one of the four battleships he wanted to take out of mothballs. But Congress has just deleted funds for one of the others, the Missouri. This appears to be a prudent, not necessarily final step in the midst of debate over the magnitude of military spending and whether funding for up-to-date airpower, say, would be wiser than for a refurbished relic of previous wars.
Mr. Reagan says he doubts there is ''a better example of the cost consciousness of this administration'' than the recommissioned New Jersey. It now is said to have all the latest equipment.
Thus, in the year-end manner of overlapping history, the age of the battleship is prolonged while the age of fusion flickers on the far, far horizon.