The Dow got slammed again on Friday, dropping more than 400 points on worries about a looming trade war with China.

After ducking in and out of positive territory for much of the day, the Dow Jones industrial average tumbled in the late afternoon to close down 424.69 points at 23,533.20.

The drop capped a two-day selloff that left the blue-chip index more than 1,100 points lower, plunging the Dow to its lowest levels since November.

The broader S&P 500 and Nasdaq also saw red, ending the day, down 2.1 percent and 2.4 percent, respectively.

The Dow and S&P experienced their worst week since January 2016, down 5.7 percent and 5.9 percent, respectively. The Nasdaq shed 6.5 percent.

There was no shortage of headlines to keep markets skittish.

Early Friday President Trump tweeted he was considering vetoing an omnibus spending bill before ultimately agreeing to sign it.

“There are a lot of things I’m unhappy about in this bill,” Trump said Friday when announcing his plans to sign the bill.

When Trump eventually signed the bill, with the Dow climbed as much as 100 points in early afternoon trades.

Also on Friday China signaled that it may rethink its role as the largest foreign creditor the US and might pare back its purchases of US Treasuries in response to President Trump’s plans to tariff $60 billion of Chinese imports.

When asked by Bloomberg if China would reduce purchases of US Treasuries in response to a looming trade war, Cui Tiankai, China’s ambassador to the US, did not rule out the possibility.

“We are looking at all options,” Tiankai said in a televised interview Friday. “If a trade war is forced on us, we have to fight back.”

China holds $1.2 trillion in Treasuries, roughly 19 percent of foreign holdings of US government securities, according to government data.

The possibility of China slowing purchases poses another risk as there is expected to be a glut of Treasuries as the Federal Reserve unwinds its $4.4 trillion balance sheet. Recent tax cuts and the $1.3 trillion omnibus spending bill means Treasury will need to sell more securities to keep the government running.

“With China potentially not being there as a buyer, supply and demand is skewed,” Mona Mahajan, US investment strategist of Allianz Global Investors, told The Post.

But for all the seeming bluster, Wall Street was skeptical about China’s threats.

“We’re not surprised they’re talking the talk, “ Mahajan said.

“Much of the noise coming out of Washington and China is posturing,” Bruce Bittles, chief investment strategist at RW Baird, told The Post.

Bittles added that China likely doesn’t want to hurt its biggest market for manufactured goods.

China would also have trouble finding cheap other safe havens to park their money.

“The US is still the de facto currency. It’s a place where China can keep its money and sleep well at night,” Mahajan said.

“They don’t want to escalate this trade war,” Mahajan said, noting that China issued a “measured response” to tariff only $3 billion of US imports after President Trump said Thursday he was tariffing $60 billion of Chinese imports.