President Donald Trump and Democratic rival Joe Biden both say they want to pull U.S. forces out of Iraq and Afghanistan. But their approaches differ, and the outcome of the November 3 election will have long-term consequences not only for US troops, but for the wider region.

During his election campaign four years ago, Trump pledged to bring all troops home from “endless wars,” at times triggering pushback from military commanders, defense leaders and even Republican lawmakers worried about abruptly abandoning partners on the ground. In recent months he has only increased the pressure, working to fulfill that promise and get forces home before Election Day.

More broadly, Trump’s ‘America First’ mantra has buoyed voters weary of war and frustrated with the billions of dollars spent on national defense at the expense of domestic needs. But it has also alienated longtime European partners whose forces have fought alongside the United States, and has bruised America’s reputation as a loyal ally.

Biden has been more adamant about restoring US relations with allies and NATO, and his stance on these wars is more measured. He says troops must be withdrawn responsibly and that a residual force presence will be needed in Afghanistan to ensure terrorist groups can’t rebuild and attack America again. That approach, however, angers progressives and others who believe the US has spent too much time, money and blood on battlefields far from home.

“We’re getting out of the endless wars,” Trump told White House reporters recently. He said the “top people in the Pentagon” probably don’t love him because “they want to do nothing but fight wars so that all of those wonderful companies that make the bombs and make the planes and make everything else stay happy.”

He continued: “Let’s bring our soldiers back home. Some people don’t like to come home. Some people like to continue to spend money.”

Biden, the former vice president, has sounded less absolute about troop withdrawal. In response to a candidate questionnaire from the Center for Foreign Relations, he said some troops could stay in Afghanistan to focus on the counterterrorism mission.

“Americans are rightly weary of our longest war; I am, too. But we must end the war responsibly, in a manner that ensures we both guard against threats to our homeland and never have to go back,” he said.

While both talk about troops withdrawals, each has, in some ways, tried and failed.

Trump came into office condemning the wars and declaring he would bring all troops home. When he took over, the number of forces in Afghanistan had been capped at about 8,400 for some time by his predecessor, President Barack Obama. But within a year that total climbed to about 15,000, as Trump approved commanders’ requests for additional troops to reverse setbacks in the training of Afghan forces, fight an increasingly dangerous Islamic State group and put enough pressure on the Taliban to force it to the peace table.

Biden was part of the Obama administration’s failed effort to negotiate an agreement with Iraqi leaders in 2011, and as a result the US pulled all American forces out of that country. That withdrawal was short-lived. Just three years later, as IS militants took over large swaths of Iraq, the US again deployed troops into Iraq and neighboring Syria to defeat IS.

With an eye toward the election, Trump has accelerated his push to bring troops home. Gen. Frank McKenzie, the top US military commander for the Middle East, said in recent days that by November, the number of troops in Afghanistan could drop to 4,500, and the number in Iraq could dip from about 5,000 to 3,000.

John Glaser, foreign policy director at the Cato Institute, is skeptical of both candidates. He said Biden, if elected, will struggle with pressure to pull troops out, but will be drawn to getting things back to normal, “which means being there for allies, reupping our commitment to NATO.”

Glaser said he believes Trump really wants to pull troops out, but is driven by his electoral self-interest. “He wants to get out but he doesn’t know how to do so in a way that doesn’t feel like tucking tail and running.”

He added that if Trump is reelected, “I’m a little nervous that he will lose a little electoral incentive. If there aren’t votes to be against I frankly don’t know what he will do. He could slip into another conflict, given his belligerence on any given issue.”

McKenzie and other military leaders, however, have consistently argued that conditions on the ground and the activities of the enemy must dictate troop levels. They suggest that the US must keep troops in the region to ensure enemies don’t regain a foothold.

Michele Flournoy, a former top Pentagon leader who is often mentioned as a potential defense chief in a Biden administration, warned against any “precipitous” withdrawal from Afghanistan that could jeopardize peace. In remarks to the Aspen Security forum, she said that while the US doesn’t want to be in Afghanistan forever, a counterterrorism force should remain until a peace agreement between the Taliban and the Afghan government is solidified.

Rep. Mac Thornberry of Texas, the top Republican on the House Armed Services Committee, said Trump will provide more money for the military while the Democrats probably will try to cut the defense budget. But he also echoed troop withdrawal concerns, reflecting a broader reluctance on the committee to abandon Afghanistan while the Taliban continue to launch attacks and a stubborn IS insurgency threatens to take hold.

“Everybody wants to be able to bring troops home from Afghanistan and elsewhere. I think the differences are largely about whether you only do it when certain conditions are met or whether you withdraw anyway and hope for the best,” said Thornberry. “Really what I’m thinking of is the way President Obama withdrew from Iraq. … We withdrew and kind of said ‘Good luck.’ Obviously, things did not go so well.”