President Trump plans to propose a reorganization of the federal government as early as Thursday that includes a possible merger of the Education and Labor Departments, coupled with a reshuffling of other domestic agencies to make them easier to cut or revamp, according to administration officials briefed on the proposal. Mr. Trump and his budget director, Mick Mulvaney, the architect of the plan, have sought to redefine as welfare subsistence benefit programs like the Supplemental Nutrition Assistance Program, or SNAP, and housing aid. It is part of a rebranding effort, championed by conservative think tanks and House Republicans, to link them to unpopular direct-cash assistance programs that have traditionally been called welfare.“They have been using the word welfare because it is pejorative,” said Elaine Waxman, a senior fellow in the Income and Benefits Policy Center at the Urban Institute, a nonpartisan Washington think tank. “The programs you can call welfare are actually very small in comparison to SNAP, which is an income support necessary to help families, workers and millions of kids.”At the heart of the plan is expected to be an attempt to shift SNAP, which serves more than 42 million poor and working-class Americans, to the new agency from the Agriculture Department. Conservative think tanks, including the Heritage Foundation and Koch-related entities, have long sought to de-link food aid from agriculture in hopes of cutting costs.