Answer to Question 1
The APHIS monitors potential threats by pests to humans as well as other wildlife, monitors noxious weeds, monitors the use and safety of engineered species, and monitors the effort to reduce diseases in wildlife.
U.S. federal agencies collaborate with other countries to prevent the spread of pest organisms. The International Plant Protection Convention (IPPC) ratified by the United States in 1972 set up an international system to quarantine products to prevent pest spread.
Answer to Question 2
Under the current economic paradigm, sustainable development is an oxymoron because the development model of the last century or more has been dependent upon continued growth; when growth ends, a recession begins. In many ways it is essential that humans develop an economic system that does not require constant growth because constant growth conflicts with natural systems. For example, uncontrolled cell growth is cancer. If taken to its logical extreme our current economic system results in the destruction of natural systems. There is no economic gain associated with not polluting the environment or removing resources at a rate that does not exceed their replacement. Because many industrial processes rely on clean air and/or clean water, polluting these is economically damaging. Yet at the same time there are economic advantages to be gained with releasing wastes into water or air because the cost to clean these resources is not borne by the polluter.
Civilization will not continue without sustainable development. If our current goods and services are produced in a way that destroys the environment, the goods and services provided by the environment will be destroyed and our standard of living will collapse. Therefore, continuation of an economic system that requires continuous growth will result in primitive living. The only hope for maintaining our standard of living (health care, education, physical comfort) is to create a way of life that lives within the resources that are available.