JEFFERSON CITY, Mo. (AP) — President Donald Trump wants to rebuild the nation's transportation infrastructure. He also wants to strengthen the U.S. steel industry through tariffs on imports.

But that second goal could make it more costly to accomplish the first.

Since Trump announced the tariffs in March, prices have been rising for the American steel used to build bridges, reinforce concrete highways and lay the rails for mass transit systems. Though many of this summer's big construction projects had locked in pre-tariff prices, concerns are mounting among contractors and some transportation...