OMAHA, Neb. & INDEPENDENCE, Ohio--(BUSINESS WIRE)--The International Association of Sheet Metal, Air, Rail and Transportation Workers – Transportation Division (SMART-TD), the nation's largest railroad union, and Union Pacific Railroad, the nation's largest railroad, today announced a historic agreement ensuring job security for thousands of railroad workers as Union Pacific and Norfolk Southern pursue a proposed merger. This groundbreaking agreement guarantees that SMART-TD members working in. ...