President Donald Trump brought back up the idea of American-made iPhones on Friday when he threatened a 25% tariff on Apple.

New tariff threats aimed at Apple, Europe send markets tumbling, an AP business editor explains. (AP video by Mike Householder)

US stock futures were at a standstill as Wall Street looked forward to wrapping up a week marked by growing doubts about the economy's health under Trump's trade and tax agendas.

As this special report shows, financial innovation has transformed Wall Street. As in eras past, surging asset values have concealed cracks in the new financial order. Whatever dangers are lurking, Mr Trump’s presidency will make them more dangerous still. ■

Newly sworn-in Social Security chief Frank Bisignano, who previously was a Wall Street executive, told staffers he had to Google the SSA job when it was offered to him.

"Major financial events often happen first in Japan, for example the late-1990s tech bubble bursting first in Japan," Albert Edwards wrote Thursday.

Wall Street slumped under the weight of pressure from the bond market, where Treasury yields climbed on worries about the U.S. government’s spiraling debt and other concerns.

Wall Street, however, has calmed down. And it was not so panicked in the first place. During the recent turbulence, the VIX, a fear gauge, hit only its 24th-highest monthly level in the past 35 years. The index measures expected volatility for American stocks, based on the price investors pay for insurance.

Residents balked at a small traffic circle at Greenlawn Avenue and Wall Street near Potawatomi Park, saying it may worsen traffic.

Bond yields inched higher and Wall Street flipped from small gains to losses before the opening bell Thursday after rising U.S. debt sank markets on the previous day. Futures for the Dow Jones Industrial Average fell 0.5% in premarket trading, while futures for the S&P 500 and Nasdaq each slid 0.3%.