General Electric Co. is girding for a showdown with Wal-Mart Stores Inc. over a proposed U.S. tax on imports, setting up a battle across industries that could be one of the most fractious in recent corporate history.

GE, Dow Chemical Co., Eli Lilly & Co. and about 20 other companies joined the American Made Coalition, a group representing makers of domestic goods that will promote efforts to overhaul the U.S. tax code. They say the so-called border-adjusted tax would help U.S. manufacturers compete with products made overseas, giving a boost to President Donald Trump's goal of increasing factory jobs.

The battle is opening up a fault line in corporate America, with net importers mostly on one side and exporters on the other. Billions of dollars are at stake: The proposed overhaul of the corporate tax code, supported by House Speaker Paul Ryan, would reward companies that sell products outside the U.S. while punishing those that rely on low-cost overseas suppliers.