The superpower’s engineers and soldiers waded into the waves lapping at the Mediterranean shoreline and tethered their pontoons to form a sort of pier, eventually to become a bridge. But a storm wrecked the pier and delayed the superpower’s plans. Those ultimately turned out to be doomed anyway.

You’re probably recognizing the start of Herodotus’s account of the Persian attempt to cross the Hellespont in 480 BCE. I couldn’t help but think of it when a storm recently buffeted and disabled the pier that the United States was building on the coast of the Gaza strip.

Within weeks of that setback, the Americans, like the Persians of yore, rebuilt their floating structure. But it’s still not being used the way it was intended. Cindy McCain, widow of the former senator and head of the World Food Program, said this week that it’s not safe to unload humanitarian provisions there, after rockets hit nearby warehouses and injured staff. That also means the U.S. Agency for International Development, which coordinates with the WFP, is pausing its efforts.

The floating pier was an idea that President Joe Biden announced in his State of the Union address in March. He gave that speech five months to the day after Hamas massacred Israelis in the worst slaughter of Jews since the Holocaust, and almost as long after Israel began bombing the entire Gaza strip into rubble, while often hindering the humanitarian aid meant to succor its 2 million civilians.

Throughout that time and the three months since, Biden hasn’t been able to change the situation for the better. To his credit, he’s kept the conflict from spreading into a regional war between the U.S. and Iran. But he hasn’t deployed the full power of the Oval Office to restrain or guide the Israeli government, nor to lean on both Hamas and Israel, via their intermediaries, to agree a ceasefire that would free the hostages and prepare the eventual reconstruction of the Gaza strip.

Pleasing neither side, Biden has instead resorted to largely symbolic half-measures. When the Israelis held up aid supplies on land, he ordered a few loads to be dropped by parachute. When they kept dropping tunnel busters, he blocked one shipment of the most explosive bombs going to Israel, while continuing to supply it with all the other weapons that America gives Israel.

This week, in what must pass for a diplomatic win, Biden finally pushed a U.S.-drafted resolution through the United Nations Security Council. It calls on Hamas and Israel to accept a ceasefire agreement that Biden recently sketched out. But its language was diluted enough to satisfy few and offend many, while not necessarily bringing peace any closer.

The most tangible symbol for American fecklessness is that pier. When I first heard Biden describe it during the SOTU, I thought of other heroic American feats of logistics. During the Berlin airlift of 1948-49, for example, the Americans and their British allies fed half a city for almost a year, at the risk of sparking World War III, until the adversary yielded in the face of such awe-inspiring American resolve.

Biden’s pier operation, by contrast, is well-meaning and ambitious, though hardly on the epic scale of 1948 (or 480 BCE). Massive amounts of victuals and medicine first go to Cyprus, then to an offshore platform where they are reloaded onto vessels to the pier. From there, they’re meant to travel by truck, under U.N. supervision, throughout the Strip.

That’s the theory, at least. In practice, only a few dollops have arrived in the Gazan interior, often to be looted. During the brief time the pier was working before the storm, about 27 trucks a day left from it, with planning for 150; the Gaza strip apparently needs at least 600 a day to escape famine. This pier is hardly the humanitarian equivalent of a D-Day beachhead.

As Herodotus told his anecdote about the Persian setback, King Xerxes, who was on the way to conquering the Greeks, was so full of hubris that he gave orders to whip the Hellespont’s waves with 300 lashes and to scald the water with hot irons as punishment. The sea was unimpressed, and Xerxes, as Herodotus’s audience understood, already doomed.

The U.S., as a long-in-the-tooth superpower, also succumbs to hubris from time to time, thinking that it can or should solve every problem. Unlike Xerxes, though, Biden yearns to use whatever remains of his country’s power for good. It’s just that he keeps learning that the world and its many hatreds, like the Hellespont, won’t be tamed, by him or any president.

At worst, Biden’s pier, long before it does any good, becomes a target for the region’s terrorist groups, drawing the U.S. deeper into the fighting. At best, the pier operates for a while longer with negligible impact, until it becomes irrelevant once Israel and some outside coalition of custodian powers restore adequate humanitarian access by land.

Herodotus’s story moved his audiences because they knew what came next: The Persians lost, and on their way home discovered that their rebuilt bridge was in ruins yet again. The Achaemenid dynasty began its decline; one-and-a-half centuries later, Alexander the Great crossed the Hellespont in the other direction and dissolved the Persian Empire.

The U.S. is not, or not yet, in danger of such a fate. But Biden and his successors would do well to accept that Washington can’t solve every problem and must choose judiciously where and how to intervene, and then with full commitment rather than symbolic gestures. Xerxes, incidentally, had no good reason to be in Greece at all. Whenever the current conflict in the Middle East winds down, the U.S. might do well to leave that region and stay gone.

Andreas Kluth is a Bloomberg Opinion columnist covering U.S. diplomacy, national security and geopolitics. Previously, he was editor-in-chief of Handelsblatt Global and a writer for the Economist.