this is from the NYS DMV site...
QUOTE
International Driving Permit: An International Driving Permit is not a driver license. The permit only verifies that you hold a valid driver license in your home country. Your foreign driver license, not the International Driving Permit, allows you to drive in NYS. Contact the authorities in your home country to get an International Driving Permit. If you are not a resident of the US, you cannot apply for an International Driving Permit in the US.
You are not required to have an International Driving Permit to drive in NYS, but the permit has value. The permit verifies, in several languages, that you have a valid foreign driver license. A police officer who cannot read the language on your foreign driver license can read the permit.
and this is from the CAlifornia DMV site...
QUOTE
International Driving Permits
The State of California does not recognize an International Driving Permit (IDP) as a valid driver license. California does recognize a valid driver license that is issued by a foreign jurisdiction (country, state, territory) of which the license holder is a resident.
The IDP is only a translation of information contained on a person's foreign driver license and is not required to operate a motor vehicle in California. Citations issued to a person in California who has an IDP, but does not have a California driver license will be placed on the Department of Motor Vehicle database
other States might be similar to this... you have to check out the State's DMV site to find out if they accept the International Driving permit...