Yes, the US will still talk to Iran if Iran wants to talk. No, the US won't start a war with Iran. The US will pursue what the US feels are appropriate sanctions. The Russians and Chinese probably won't go along. Israel will be free to try a naval blockade of Iran since they think that is a sanction against others and only an act of war when against Israel. It is doubtful anybody will assist Israel in the naval blockade. Iran is digging mine-shafts. Israel should be digging them too and stocking them with the people Israel has determined it needs there. (See Dr Strangelove for appropriate criteria.) The mine-shaft gap is growing! The US has extended its nuclear umbrella over Israel and no country protected by that has ever been attacked with nukes.
Russian defense ministry: Plane sent to intercept U.S. plane near border on Friday (Reuters)
from the article: Obama to Iran: Offer of dialogue still stands