actually its possible today but only if mexico or canada were some how taken over by lunatics.
But they wouldn't be successful. This is because even if a foreign state did have the military might to hold the land its taken the USA would nuke the homeland of said military.
Still this raises the question: Would the USA use nukes on Mexico or Canada if they had a war?
A Mexican Canadian alliance could cause some serious damage if the US doesn't use Nukes to settle things. I doubt they could hold out forever but a quick short term victory is possible if they can somehow figure out how to surprise the USA. i would geuss drug cartel tunnels used to sneak weapons and troops onto US soil then a sudden Blitzcrieg by tens of thousands of soldiers already on US soil. Canada rushes seattle and washington?
As to successful invasions in the past Alaska could be invaded till 1946.
States only then California could be invaded till 1920 thanks to that earthquake.
But they wouldn't be successful. This is because even if a foreign state did have the military might to hold the land its taken the USA would nuke the homeland of said military.
Still this raises the question: Would the USA use nukes on Mexico or Canada if they had a war?
A Mexican Canadian alliance could cause some serious damage if the US doesn't use Nukes to settle things. I doubt they could hold out forever but a quick short term victory is possible if they can somehow figure out how to surprise the USA. i would geuss drug cartel tunnels used to sneak weapons and troops onto US soil then a sudden Blitzcrieg by tens of thousands of soldiers already on US soil. Canada rushes seattle and washington?
As to successful invasions in the past Alaska could be invaded till 1946.
States only then California could be invaded till 1920 thanks to that earthquake.