[jmcomets]

Just adding to this for the uninitiated-but-curious: the German army invaded by going around the line. This meant taking tanks through the Ardennes, a bordering region consisting of mountains and forests, not quite the Panzer's ideal terrain...

Nowadays it's still used as a French expression to describe a "seemingly impassable defense that's useless in the end".

[iso1631]

One thing I read recently said one of the aims of the maginot line was to delay the Germans (it did -- they had to go through NL/BE), and another was to ensure they went through BE and thus brought the British in to the fight (due to a UK/BE defence guarantee). It did that too.

[dmichulke]

I think the British also guaranteed Poland, so they we're already in in September '39