WASHINGTON'S reaction to New Delhi buying two light water nuclear reactors from Moscow was surprisingly muted. A spokesman from the State Department's South Asia Bureau, when pressed for comments, was cryptic: "We believe Russia should limit sales of nuclear reactors to countries with full-scope safeguards as it agreed to do when it joined the Nuclear Suppliers Group." The spokesman would not say whether the issue cropped up during the recent Yeltsin-Clinton summit. "It might have, I have no idea specifically if it did," he said.