I wrote a letter tonight about the rising radicalism of the Republican Party. But then, sorting through the dark chaos of today’s news, I found myself thinking instead about the Battle of Mobile Bay, which happened on this date in 1864.

By the spring of 1864, victory in the Civil War depended on which side could endure longest. Confederates were starving as they mourned their many dead; Union supporters were tired of losing sons to battles that seemed to accomplish nothing. President Abraham Lincoln knew he must land a crushing blow on the South or lose the upcoming presidential election. If he lost, the best Americans could hope for was a negotiated peace that tore the nation in two. In March 1864, Lincoln appointed Ulysses S. Grant commander-in-chief of all the Union armies, hoping that this stubborn westerner could win the war.

Grant set out to press the Confederacy on all fronts. In the past, the Union armies had acted independently, permitting Confederates to move troops to the places they were most needed. Grant immediately coordinated all the Union armies to move against the South at once.

In the East, the Army of the Potomac would hit Robert E. Lee’s Army of Northern Virginia. In Georgia, William T. Sherman’s western troops would smash their way from Tennessee to Atlanta. Finally, Grant wanted the U.S. Navy to move against Mobile, Alabama, a port on the Gulf Coast so well protected by shifting sands that it had become the major harbor for the blockade runners that still linked the Confederacy to Europe. Grant hoped this strategy would lock the South in a vise.

By midsummer, the plan had faltered. The Army of the Potomac had stalled in Virginia after an appalling 17,000 casualties at the Battle of the Wilderness, 18,000 at Spotsylvania, and another 12,000 at Cold Harbor, where soldiers pinned their names and addresses to the backs of their uniforms before the battle so their bodies could be identified. Sherman was stopped outside Atlanta. And the navy had run aground up the Red River in Louisiana as it made a feint in that direction before the move against Mobile Bay. Union morale was so low that even President Lincoln thought he would lose the election and the war would end in an armistice.

By late summer, the pressure was on Admiral David G. Farragut to deliver a victory in Mobile Bay. After weeks of waiting for reinforcements, on the morning of August 5, Farragut ordered the captains of the fourteen wooden ships and four ironclads under his command to “strip your vessels and prepare for the conflict.” At 5:40 a.m., with the wooden ships lashed together in pairs and the ironclads protecting them, the vessels set out in a line to pass the three forts and four warships that guarded the harbor above water, and the minefield that guarded all but a 500-yard channel below. The admiral’s flagship, the Hartford, was in the second pair in line, behind the Brooklyn and its partner.

As the ships proceeded under heavy fire, going slowly to stay behind the lumbering ironclads, the foremost ironclad hit a torpedo, turned over, and sank instantly, taking all hands with it. Aware he was on the edge of the minefield, the commander of the Brooklyn hung back, throwing the whole line into confusion under the pummeling of the land batteries. Farragut ordered the captain of the Hartford to take over the lead. As the Hartford passed the stalled Brooklyn, the Brooklyn’s captain warned that they were “running into a nest of torpedoes.”

“Damn the torpedoes!” Farragut allegedly shot back. “Full speed ahead!”

By 10:00 a.m., the U.S. Navy had taken Mobile Bay, cutting off all Confederate contact with Europe. It was the victory the Union needed, and others followed in its wake: Atlanta fell on September 2, and the Army of the Potomac began to gain ground in Virginia. Finally able to believe that victory was near, voters rallied behind Lincoln’s determination to win the war and backed his administration in November. They gave him 55% of the popular vote and gave the Republicans supermajorities in both the House and the Senate.

Damn the torpedoes, indeed.