Navel blockade of Afganistan doesn't make much sense anyway
Though apparently there are provisions in the treaties to cover blockades of land locked nations.
More to the point, there is an obvious gap in the treaty over time frames. The treaty doesn't say anything about response times or how long the Security Council has to act or how long your are justified in retaliating after an attack.
You obviously can't read it as being an elaborate game of green light/red light where you have to stop the moment the other side says they are stopping. But at the same time you can't sensibly read it as lasting forever either, Iran can't justify invading Iraq now over the invasion Saddam ordered of Iran.
Ultimately it's a matter of political pressure.
Jay