The 3rd Annual Lost Voices of Fentanyl Rally: The Dead Speak — highlighting the more than 70,000 dying annually from this synthetic opioid sourced in Communist China — will on Saturday assemble at the Washington Monument and march on the White House, hoping to “wake up” the Biden Administration and Republicans in Congress.

Fentanyl is a geopolitical and national security threat different from previous battles in the drug war, with Beijing weaponizing it against America. “The West once flooded China with opium,” as the Economist wrote in 2018. “China is returning the favor.”

The founder of Lost Voices of Fentanyl, April Babcock, buried her son, Austen, 25, in 2019 after an overdose. Her group has grown to 30,000 members in three years, a number that indicates just how many lives have been cut short by the drug, now the leading cause of death for Americans between the ages 18 and 45.

In 2022, the administrator of the Drug Enforcement Agency, Anne Milgram, said the DEA seized “over 379 million deadly doses of fentanyl from communities across the country.” That would be, she said, enough “to kill every American” but is a fraction of what slips in undetected.

“It’s estimated China is responsible for over 90 percent of illicit fentanyl found in the United States,” a representative of Washington, Dan Newhouse, wrote in February. “After being shipped to Mexico, the chemicals are produced into fentanyl-containing tablets,” which enter America via the southern border.

Mr. Newhouse’s district borders Canada, showing the national scope of the problem. “We simply cannot allow,” he said, “the lethal fentanyl engine in China to run while communities across America’s heartland are being torn apart.”

The cost of this potent opioid is often overlooked, obscured by shame and stigma. The Lost Voices of Fentanyl Rally aims to raise the issue’s profile while reminding Mr. Biden that Americans and non-Americans alike are paying a steep cost for inaction.

In last week’s CBS/YouGov poll, 66 percent of adults disapproved of Mr. Biden’s “handling of immigration,” a close second to inflation, where the president earned his only higher negative number, 71 percent. But weak border security has impacts beyond the challenges of new arrivals.

Last month’s Center Square Voters’ Voice Poll found that 57 percent of registered voters are “very concerned” about fentanyl deaths while 32 percent are “somewhat worried.” Expect the crisis to loom large in the 2024 election.

An author speaking at Saturday’s rally, Trisha Posner, told me she and husband Gerald — an attorney and investigative journalist — have “tried to imagine how we would feel if we lost a child to this drug and how furious we would be if the government was not doing everything it could to stop the flood of fentanyl.”

In an election year, however, the White House is seeking to put its best foot forward. “To make ‘stopping fentanyl’ a top issue,” Mr. Posner told me, “would draw attention to what a terrible job it has done with allowing a record surge of illegal migrants to enter the U.S.”

This inaction “has empowered the cartels,” Mr. Posner said, “and turned hundreds of thousands of desperate migrants into drug mules.” Highlighting the issue’s orphan political status, the Republican House has “failed to pass a bill that lists the cartels as terror organizations or to list fentanyl as a WMD.”

Mr. Posner calls the lack of confronting the new Opium War “a maddening bilateral political failure.” The author of “Pharma: Greed, Lies, and the Poisoning of America,” he points out that unlike the prescription opioid scourge, “when it comes to fentanyl, parents do not even have the satisfaction of using American courts to punish any of those responsible.

“Families from all walks of life are being devastated by illicit fentanyl poisonings,” Lost Voices of Fentanyl writes on its website, and “the consequences of these losses do not end with the victims. The damage continues on, impacting the children and families left behind forever.”

Saturday’s march, Lost Voices of Fentanyl said, is about all Americans. Their message to Washington and Beijing will be that the battle has been joined, and that they’ll not stand silent while poison steals away their family, friends, and neighbors.