5 major threats to US national security in 2024

The new year is looking to be a tumultuous one for U.S. security, with ongoing conflicts in Ukraine and Israel, growing unrest in the Middle East and Indo-Pacific, and an upcoming presidential election that may stir domestic strife.

The Department of Homeland Security (DHS), in its Homeland Threat Assessment for 2024 released in September, predicted a slew of issues staring down the country. 

Those include terrorism both foreign and domestic, adversaries targeting critical infrastructure, an aggressive China and an election cycle that “will be a key event for possible violence and foreign influence targeting our election infrastructure, processes, and personnel.” 

Here are five major threats to U.S. security to watch closely in 2024. 

Expansion of Israel-Hamas war 

The fight between Israel and Hamas in the Gaza Strip has shown no sign of slowing down since the Palestinian terrorist group first attacked the country Oct. 7, triggering a brutal Israeli air and ground campaign in retaliation.  

Gaza’s health ministry estimates more than 22,000 Palestinians have been killed in Gaza since Oct. 7 — more than two-thirds of them women and children. The human toll has enraged nearby Arab nations including Iran, Lebanon, and Houthis in Yemen — and upped pressure from the West to scale back the war. 

The conflict several times has threatened to tip into a wider war that engulfs the Middle East, most recently with an attack on a Hamas office in Lebanon that killed a senior leader of the group Tuesday.  

Lebanese Prime Minister Najib Mikati called it a “new Israeli crime that aims to drag Lebanon into a new phase in confrontations.” 

In the Red Sea, escalating Houthi attacks on cargo ships — at least 17 so far — have disrupted key global shipping routes and stoked fears that the United States could get pulled into a larger conflict.

Washington late last year assembled a multinational naval coalition to offer protection to shipping vessels traveling through the region, but President Biden has stressed he wants to avoid direct military confrontation with the Houthis. 

That changed Sunday, when U.S. Navy forces sunk three Houthi boats that attacked a container ship, killing all crew on the vessels.  

U.S. forces also continue to come under attack at outposts in Iraq and Syria, with dozens of rocket or drone attacks aimed at American troops in response to Washington’s support for Israel in its war against Hamas. 

Conflict over Taiwan  

Even after a high-profile meeting between Biden and Chinese President Xi Jinping in November, tensions continue to simmer over the self-governing island of Taiwan, which China hopes to bring it under its control. 

Those tensions have spiked ahead of the Jan. 13 Taiwanese presidential and parliamentary election, which the United States is watching closely. 

While Washington ostensibly recognizes Beijing’s “One China” policy, it provides major support to Taipei and is legally bound to provide the island with weapons and equipment to defend itself. 

Under Xi, China has steadily increased pressure on Taiwan via intense war games and other military activity around the island. The U.S., in turn, has increased its naval transits through the Taiwan Strait, which China maintains that it controls. 

Biden on several occasions has also said that Washington would defend Taipei should Beijing seek military conflict. 

The tit-for-tat reached a crescendo in August 2022, when then-House Speaker Nancy Pelosi (D-Calif.) visited Taiwan, prompting a retaliation from China that included a massive military exercise, firing missiles over the island, and cutting official military communication channels with the Pentagon. 

The communication channels have since been restored, but Xi has only doubled down on his ambitions on Taiwan. 

“The reunification of the motherland is a historical inevitability,” Xi said in his New Year’s address Sunday.  

Expansion of Russia-Ukraine war 

Washington continues to provide Ukraine with billions of dollars’ worth of equipment and military expertise in its fight with Russia, but U.S. public support for the war has frayed in the past year — and Russian President Vladimir Putin stands to benefit. 

“Russian messaging has focused on justifying its aggression, seeking to reduce US domestic support for Kyiv, and encouraging divisions among the diverse set of global partners that are helping Ukraine,” according to DHS.  

Malicious cyber activity targeting the United States has increased since the beginning of the Russia‑Ukraine conflict, and DHS expects that to continue as the war drags on. 

“Pro‑Russia cyber criminal groups, such as Killnet, collaborate to conduct distributed denial‑of‑ service (DDoS) attacks and other potentially disruptive attacks against US government systems and our transportation and healthcare sectors,” according to the threat assessment report.  

Moscow has also started the new year with an intense bombardment campaign against Ukraine, most recently hammering Kyiv with missiles and drones Tuesday morning. 

The large-scale attack, which included several other cities and about 100 missiles, killed at least five people and injured nearly 130 others and is part of a deadly aerial tit-for-tat between the two countries.  

The latest air campaign has already threatened to pull in NATO, when a Russian missile Friday breached member Poland’s airspace, according to the Polish military.  

Earlier that same day, the United States and Poland scrambled F-16 fighter jets to counter a long-range Russian aircraft, Poland’s Armed Forces Operational Command wrote on X, formerly known as Twitter. 

Domestic extremist group attacks 

Attacks on the homeland by domestic extremist groups have been on the rise in the last several years, spurred on by political strife, conspiracy theories, overseas wars and other tensions.  

Several attacks widely reported in the last few years include the May 2022, racially-motivated killing of 10 people in Buffalo, N.Y., all of whom were Black. And in 2018, an attack on a Pittsburgh synagogue left 11 people dead.  

Over the last 10 years, domestic terrorism-related investigations have grown by 357 percent, according to a March assessment by the Government Accountability Office.  

DHS assessed that the next year will continue to see a high threat of violence from individuals radicalized in the United States, “marked by lone offenders or small group attacks that occur with little warning.” 

“These actors will continue to be inspired and motivated by a mix of conspiracy theories; personalized grievances; and enduring racial, ethnic, religious, and anti-government ideologies, often shared online,” according to the threat assessment report. 

Since January 2022, domestic violent extremists have conducted three fatal attacks in the United States, resulting in 21 deaths, as well as multiple nonlethal attacks. U.S. law enforcement has disrupted more than six other plots during that time. 

During the same period, only one individual conducted an attack inspired by a foreign terrorist organization. 

Outside election interference

In the 2020 presidential election, national security officials had to contend with a slew of concerns — potential cyberattacks targeting voting infrastructure, threats against poll workers and officials, outside foreign influence and other actors looking to undermine confidence in the election outcome. 

Many of these concerns still persist this time around, according to DHS. 

“We expect the 2024 election cycle will be a key event for possible violence and foreign influence targeting our election infrastructure, processes, and personnel,” states the DHS Homeland Threat Assessment report.  

Microsoft, in a November threat assessment, warned that the 2024 election “may be the first presidential election during which multiple authoritarian actors simultaneously attempt to interfere with and influence an election outcome.” 

National security experts have for years warned that foreign governments, mainly Russia, China and Iran, seek to destabilize the United States via its elections. 

That was on full display in 2016, when Russia tried to interfere by hacking into Democratic emails and releasing them, a move meant to tip the election toward Donald Trump, the eventual president. Moscow also scanned state voter registration systems seeking vulnerabilities. 

Four years later, Iranian hackers obtained voter data and used it to send deceptive emails. And in 2022, hackers linked to Russia, Iran and China multiple times breached election infrastructure and spread misinformation. 

Those incidents are only likely to ramp up as the November election nears, according to DHS.