Idea for new way to "capture" a country

I think it would be fun if once you create a defense line surrounding a country, you capture it. Of course this is not very effective against another player most times, as they can just attack the wall and break it. Where it would be useful is when you want to block a player from getting reinforcements in a country, or even just taking a whole country. Yes this method would take all the cities in the country. Well that's my idea... thanks for reading.

No, this is silly, image walling a city with 100 units in it and you destroying them all and taking the whole country. no, just no

tunder: there could be trade lanes, like roads that if you stand in there way they lose income, or if you blcok a port, the same think happens. might be cool, just way to complicated to implement, and not worth the hassle

One word for this >>> NO <<<