As the war between Israel and Hamas enters its third week, President Joe Biden is walking a tightrope and trying to accomplish three objectives simultaneously: ensure Israel has everything it needs to defend itself in what Israeli defense officials admit will be a long and grueling campaign; remind the Israelis that civilian casualties in the Gaza Strip should be kept to an absolute minimum; and prevent the Israel-Hamas conflict from spiraling into a regional conflagration.

It’s the geopolitical equivalent of a high-wire act, and success is by no means assured.

To date, the Biden administration has managed to thread the needle decently enough. The Israeli military not only has the equipment, military platforms and personnel to take the fight to Hamas but also has spent weeks hammering Gaza with thousands of airstrikes. Hundreds of thousands of Israeli ground troops are stationed near the Israel-Gaza border waiting for the order to root out Hamas infrastructure and kill the organization’s political and military leadership. According to a running tally by The New York Times, 13 Hamas officials have been killed since Israel began bombarding Gaza on Oct. 7.

The second objective, limiting Palestinian civilian casualties, has been less successful. The Israelis are dealing with an extremely complicated operational environment, with Hamas militants setting up their positions amid civilians. Gaza is one of the most densely packed places in the world, and the Palestinians who call Gaza home are limited in where they can go. Due to strict border security measures from Israel and Egypt, the more than 2 million Palestinians in the area are in a state of desperation. They have two options: Stay in their homes and hope they don’t get bombed and buried under the rubble or flee south, as the Israeli army has instructed, and risk getting killed along the main evacuation routes. That Hamas has apparently blocked some Palestinians from leaving Gaza’s northern half only adds to the misery, as does Israel’s initial decision to cut off food, water and fuel supplies to the area.

While humanitarian aid has finally crossed the Rafah border crossing into Gaza, this good news is belied by the fact that three to four dozen trucks filled with aid are woefully insufficient to deal with the desperation in the enclave. Biden and his aides will need to continue leaning on Israel and Egypt to accelerate the aid shipments. This becomes even more urgent after Israeli ground troops enter Gaza in large numbers.

In terms of direct U.S. security interests, the escalation piece of the puzzle is by far the most important. Thus far, the U.S. has tried to contain the fighting through a mixture of deterrence and dialogue: deploying U.S. military assets in the region and using ties with regional partners to send Iran and Hezbollah the message, “Don’t get involved.”

On Oct. 14, Defense Secretary Lloyd Austin ordered the deployment of a second carrier strike group, the USS Dwight D. Eisenhower, to join the USS Gerald R. Ford in the eastern Mediterranean Sea. On Oct. 17, 2,000 U.S. military personnel received “prepare to deploy” orders, military jargon for “get ready to move if we order you to move.” And over the weekend, Austin sent another Terminal High Altitude Area Defense antimissile defense system to the Middle East as well as several additional Patriot missile system battalions.

Even so, U.S. officials are still worried that escalation is a real and pressing issue. “We are concerned at the possibility of Iranian proxies, escalating their attacks against our own personnel, our own people,” Secretary of State Antony Blinken said on Oct. 22. Austin had a near-identical assessment: “We’re concerned about potential escalation. In fact, what we’re seeing is a prospect of a significant escalation of attacks on our troops and our people throughout the region.”

Austin is right but only to a point. There isn’t a prospect of significant escalation against U.S. troops — the significant escalation has already occurred. Several attack drones from Iranian-supported Shia militias targeted U.S. bases in the region last week, from the al-Tanf base in eastern Syria to a facility near Baghdad’s international airport — the first such attacks since March. The USS Carney, a warship that was traveling through the Suez Canal, intercepted a volley of drones and missiles that were launched by the Houthis in Yemen, presumably in the direction of Israel. There was another attack on U.S. troops in Syria on Monday morning, although no injuries were reported.

Then there’s Hezbollah, the terrorist group that dominates southern Lebanon and has become a kingmaker in Lebanese politics. As bad as Hamas is, Hezbollah is even worse and boasts formidable military capability. Indeed, Hezbollah is more like a quasi-army than a terrorist group. It has tens of thousands of fighters with extensive experience training other Iranian-backed proxy groups in the region and a missile arsenal that might be as high as 150,000. Some of those missiles are precision-guided and can reach all of Israel’s territory.

If Hezbollah chooses to get involved in a significant way, Israel would be forced to fight on two fronts, something it hasn’t had to do since 2006, when Hezbollah was far less capable than it is today. Israeli and Hezbollah forces have engaged in limited cross-border fire for more than a week, with fatalities registered on both sides.

Israel’s generals will have late nights in the days and weeks ahead. But so will America’s diplomats, who will be responsible for achieving goals that are no less vital: Stand by Israel as it pursues the dismantling of Hamas, even while continuing to maintain communication with all the potential combatants in the hopes of ensuring an already-tragic war doesn’t get even worse.

Daniel DePetris is a fellow at Defense Priorities and a foreign affairs columnist for the Chicago Tribune.