The Pentagon in Washington. (Charles Dharapak/AP)

In his May 20 Sunday Opinion essay, “New nukes is good nukes for Pentagon,” Walter Pincus described how the Pentagon is trying to persuade Congress to add even more money to what is already an obscenely bloated Pentagon budget, this time for new submarine-launched, low-yield nuclear weapons. Would someone please tell the American people — and Congress — that a “low-yield” nuclear weapon is, in fact, about the same power as the bombs that we dropped on Hiroshima and Nagasaki? The likelihood that such weapons would be used, once deployed, is high. Besides the terrible destruction in any single use, submarine-launched low-yield nuclear weapons increase the likelihood of a catastrophic nuclear war. Congress should refuse to fund this weapon.

Jean Athey, Brookeville

The writer is a member of Peace Action Montgomery.

Walter Pincus took Pentagon officials to task for “telling some pretty tall tales” regarding the need for low-yield nuclear warheads on U.S. submarine-launched ballistic missiles. His argument missed the target.

Russia possesses more than 2,000 non-strategic nuclear weapons. Russian President Vladimir Putin’s revanchist foreign policy and aggressive nuclear doctrine challenge the credibility of U.S. threats to respond if NATO allies are attacked. Making deterrent threats credible is difficult because the interests at stake may appear less than vital. Would the United States risk losing New York to save Paris?

As Thomas Schelling noted decades ago, credible deterrence requires that “the punishment fit the crime, not only in scope and intensity but in symbols and association.” Retaliation should be discriminate and proportionate. Responding with high-yield nuclear weapons would be neither. Responding with low-yield weapons is far more credible. Mr. Pincus was surprised that Air Force Gen. John E. Hyten said he would not launch a nuclear response immediately if one or two weapons were launched at the United States, but waiting to assess the consequences is the only sane response when faced with escalating nuclear war. Crossing the nuclear threshold should not be synonymous with nuclear Armageddon. Schelling reminded us that finding ways to terminate a limited nuclear war will be as important as how to initiate it. Reducing collateral damage helps.

Dean Wilkening, Washington

The writer formerly worked on U.S. nuclear strategy at the Rand Corp.