The United Steelworkers’ long history of influencing Wall Street mergers

When President Biden spoke out Thursday against Japan-based Nippon Steel's planned $14.9 billion acquisition of U.S. Steel, it was a win for the United Steelworkers union — it's been blasting the deal for months.Why it matters: The union's political influence stems from labor's heightened leverage in an election year — but a less understood factor involves the Steelworkers…