I think that our president believes that manufacturing jobs are booming and that he is the reason why. Are they and is he right? Not so much. Manufacturing jobs have increased in the last two years, but we cannot steal enough manufacturing from other nations that American manufacturing again had as much weight in the labor force as it did in the 1950s or the 70s or, probably, even the 90s. Nor will job-killing automation will stop.
Start with the numbers. Here are the changes in total manufacturing jobs over two-year periods since 2010, when the recovery from the Great Recession was beginning. These numbers are for production and non-supervisory employees, who are 70% all of persons in manufacturing.
Increase in Manufacturing Jobs 2011-2019 Jan.
Jan. 2011 - Jan. 2013 289,000 additional jobs 3.6%
Jan. 2013 - Jan. 2015 226,000 additional jobs 2.7%
Jan. 2015 - Jan. 2017 25,000 additional jobs 0.3%
Jan. 2017 - Jan. 2019 311,000 additional jobs 3.6%
The third two years were the worst, partly because of sluggish economic growth and that was partly due to a slowing world economy. But economic growth and job adds picked up in 2017 and 2018, in part due to a one-time boost from the Republican tax cut. It is doubtful that other administration policies had a net positive effect. New tariffs protect some factories but cause others to lose access to suppliers and spark retaliatory tariffs that hurt workers at exporting factories and farms.
It is important to examine long-term numbers to answer the jobs question. The numbers are discouraging, perhaps worse than you thought. In the last twenty years, from 1998 through 2018, the number of manufacturing employees fell by 27%. That's absolute numbers. It's even worse if you think about the relative weight of manufacturing jobs within the total work force. Whilst manufacturing job totals have often declined, total jobs in America are always increasing, except in recessions. As the manufacturing work force fell by 27%, the private sector non-farm work force grew by 25.8%. So the manufacturing share plummeted.