Some emergency executive orders (not subject to congressional review) in effect.
The USA has been in such an emergency since 9-11-01: http://www.whitehouse.gov/news/releases/2001/09/20010914-4.html
EXECUTIVE ORDER 10990 allows the government to take over all modes of transportation and control of highways and seaports.
EXECUTIVE ORDER 10995 allows the government to seize and control the communication media.
EXECUTIVE ORDER 10997 allows the government to take over all electrical power, gas, petroleum, fuels and minerals.
EXECUTIVE ORDER 10998 allows the government to take over all food resources and farms.
EXECUTIVE ORDER 11000 allows the government to mobilize civilians into work brigades under government supervision.
EXECUTIVE ORDER 11001 allows the government to take over all health, education and welfare functions.
EXECUTIVE ORDER 11002 designates the Postmaster General to operate a national registration of all persons.
EXECUTIVE ORDER 11003 allows the government to take over all airports and aircraft, including commercial aircraft.
EXECUTIVE ORDER 11004 allows the Housing and Finance Authority to relocate communities, build new housing with public funds, designate areas to be abandoned, and establish new locations for populations.
EXECUTIVE ORDER 11005 allows the government to take over railroads, inland waterways and public storage facilities.
EXECUTIVE ORDER 11051 specifies the responsibility of the Office of Emergency Planning and gives authorization to put all Executive Orders in to effect in times of increased international tensions and economic or financial crisis.
EXECUTIVE ORDER 11310 grants authority to the Department of Justice to enforce the plans set out in Executive Orders, to institute industrial support, to establish judicial and legislative liaison, to control all aliens, to operate penal and correctional institutions, and to advise and assist the President.
EXECUTIVE ORDER 11049 assigns emergency preparedness function to federal departments and agencies, consolidating 21 operative Executive Orders issued over a fifteen year period.
EXECUTIVE ORDER 11921 allows the Federal Emergency Preparedness Agency to develop plans to establish control over the mechanisms of production and distribution, of energy sources, wages, salaries, credit and the flow of money in U.S. financial institution in any undefined national emergency. It also provides that when a state of emergency is declared by the President ,Congress cannot review the action for six months.