Russia & China will veto any UN sanctions that will do real damage to Iran because they do to much trade with Iran to allow it. They will support token sanctions so it looks as if they are taking it seriously but nothing to painful. Individual countries will place national sanctions of their own but just because the US or some EU countries stop their own countries doing business with Iran it doesn't bar countries like Russia or China because its not a UN issue. Sanctions also take time to do their job because Iran will defy them and at the same time they will continue to enrich uranium, develop nukes & delivery systems and by they start to feel the effect it will be to late. Also attempting to cause a revolution risks making things worse because we don't know what the new regime will be like. Diplomacy has has been been going on for 6 years and there have been UN & national sanctions time to accept we have only 2 choices. AIR STRIKES AN IRANIAN NUKE
Saudi-led planes hit Houthi-controlled government buildings (Reuters)
from the article: U.S. warns Iran: Meet nuclear obligations or face 'next step'