Bringing manufacturing back to US

 I could see the stages in which manufacturing was leaving US

-first the manufacturing scale up is left to 'tax shelters'- the countries with more favorable tax system: Singapore, Ireland, Puerto Rico.  The manufacturing   and development expertise still remains in the US, first, de-facto, then only nominally.

After the manufacturing is moved to other countries, the local US engineering expertise erodes. The people are laid off; there is no growth. No new hires. The colleges gradually stop to supply engineers as there is no jobs for them. The education system evolves to new demands, more towards environmental protection, regulatory control, etc.

Note that there is a lot of inertia in this system. However, when the people are lost, they are gone; they will not come back. They are not there. It will take perhaps a lot of money, willingness and patience to turn the tide.

 There is not only the people aspect, there is also the 'hardware'--- factories, heavy equipment, clean rooms.  Some manufacturing areas are very difficult (capital intensive) to shut down. Once it is shut down however, it is really shut down.