ephraim asculai, thank you very much for joining us. you have argued that this is a deal that is deeply flawed. what's the main problem with it in your opinion? >> the issue is going to be the search for concealed facilities, the possible search for undeclared facilities, and these an we know and we remember from the history of iran are very probable issues. and looking for these sites, for these facilities, will be a very, very difficult issue with the president's agreement. the other issue is let's say that intelligence finds out about an undeclared concealed facility. what will the parties to the agreement do? can they go and tell the iaea, and this is written in the agreement, they tell the iaea the exact source of their information. this is not always possible. >> woodruff: what about the argument of the proponents that whatever the iranians did to cheat would involve a significant amount of nuclear material that by its very nature would be indefinitely discoverable, that it's difficult if not impossible to hide radioactive nuclear