Secretary of State Antony Blinken has temporarily concluded a days-long effort with his Armenian and Azerbaijani counterparts to settle the Nagorno-Karabakh dispute. At its core, the dispute is about Azerbaijan’s claim—recognized by the international community—that Nagorno-Karabakh belongs to them based on Joseph Stalin’s gerrymandering of the Armenian-populated region a century ago. Armenians, on the other hand, say that under the Soviet constitution, they had the right to succeed from Azerbaijan, which they did via a referendum. The mountainous region’s population is Christian and has been for millennia.

In September 2020, Azerbaijani President Ilham Aliyev launched a surprise attack on the region. His forces faltered, but Turkish Special Forces and Israeli-provided drones and intelligence tipped the balance. On November 9, 2020, Russian President Vladimir Putin, Aliyev, and the Armenian Prime Minister signed an agreement, part of which guaranteed unhindered traffic between Armenia and Nagorno-Karabakh through the so-called Lachin corridor, a road controlled by Russian peacekeepers.

Beginning in December 2022, Azerbaijani militiamen, calling themselves environmental activists, blocked the road and imposed a blockade on the only route to provide food and medicine to the self-governing Christian enclave in Nagorno-Karabakh. Last month, Azerbaijan built a checkpoint to tighten further its chokehold. In nearby Goris, I met old ladies blocked from returning home by Azerbaijan for more than four months. The Azerbaijani strategy appears to be to pressure Christians to leave, and then refuse them reentry.

Both Blinken and National Security Advisor Jake Sullivan continue to push for a diplomatic solution to the siege and Azerbaijani attempts at ethnic cleansing. It fits a long pattern in the second-half of administrations in which ambitious officials attempt “Hail Mary” diplomacy in order to salvage a legacy after first failing. For Biden’s team, Iran diplomacy has failed badly, and so both Blinken and Sullivan seek a success upon which they can advance their ambitions, be they a Nobel Prize for Blinken or becoming Secretary of State or a senator for Sullivan.

Their efforts are both dangerously futile. Just as they betrayed millions of Afghans as they allowed naïveté and wishful thinking to trump an appreciation of the reality of the adversary they faced, so too do they today risk the region’s oldest Christian community and an oasis of democracy surrounded by an increasingly autocratic Azerbaijan.

If Blinken and Sullivan truly wish to demonstrate that the blockade will not work, they need to recognize history. Diplomacy alone never ends blockades.

Consider Berlin: The Truman administration demonstrated fortitude in the 1948-49 Berlin Airlift. They did not simply deplore or issue statements of “deep concern” about the Soviet blockade.

Iraqi dictator Saddam Hussein sought to starve Iraqi Kurds into submission in the aftermath of Operation Desert Storm in 1991. The creation of a safe-haven protected by a no-fly zone staved off genocide.

More recently there was the Islamic State’s siege of Kobane: What saved the Kurds there was both a willingness to fight the Islamic State, and the repeated airdrop of supplies. (That some of the Islamic State veterans ended up fighting for Azerbaijan as mercenaries is a further irony).

Perhaps Blinken can point to Tigray as the exception to the rule. The Ethiopian government lifted its siege of the state as part of the Pretoria Agreement. This may not be a good example, though, as it occurred only after several hundred thousand people starved to death. The outside world might have averted their deaths if it had airdropped supplies to bypass Nobel Peace Laureate Abiy Ahmed’s murderous blockades.

The point is this: Diplomacy only works when all parties are sincere. Aliyev has repeatedly shown himself not to be: He violated three ceasefires during the 2020 war, and has systematically sought to uproot and ethnically cleanse the region’s Armenian population since. If Blinken and Sullivan are serious about peace and ending an illegal blockade, it is time to do much, much more.

This article originally appeared in the AEIdeas blog and is reprinted with kind permission from the American Enterprise Institute.