Final answer:
Developing countries face increased food shortages due to labor shifts, greater demand for urban services, and potential trade retaliation by developed countries when they try to transition from agriculture to manufacturing with protectionist policies.
Step-by-step explanation:
One big problem that developing countries have faced when trying to shift labor from agriculture to manufacturing by protecting domestic industries is that food shortages have increased in rural areas due to a decreased workforce in agriculture. Additionally, the shift can lead to increased demand for social and governmental services in urban centers as the population moves to cities for manufacturing jobs. Moreover, in response to these protectionist policies, developed countries may retaliate by protecting their markets and products which hampers trade and further complicates economic development for the developing countries.