Mexico declares War on the Union and the Confederacy in 1863

What if Mexico declares War on the Union and the Confederacy in 1863 post Gettysburg in hopes of reclaiming some of its lost territories?
 
By Mexico, are we talking about the Empire of Mexico, or the Mexican Republic?

Because either way, it does nothing but make things worse.

Republic declares war, they will end up pissing off the USA in the post-Civil War era and will be wasting resources that could be better spent against the French.

Empire declares war, it won't change the USA's stance towards them: Lincoln had made it clear that he was sympathetic to the Republicans and distrusted the Mexican Empire. It would certainly push the USA's position from sympathetic to actively helping in the form of supplies.

There was the Hampton Roads Conference in 1865, where they discussed assisting Mexico against the French to help patch up North-South Relations, but the US is still not in much of a position to actually do so.

Regardless of which Mexico declares war on the US and Confederacy, it's ultimately meaningless and against their best interest.
 
Gets its ass kicked so hard that the French won't bother supporting Maximillian or don't even have to try to defeat Juarez. An offensive war means fighting pitched battles, which Mexico would not win against the mobilized nation and rebels to the Nortg.
 
Okay, which Mexico is declaring war, and while their troops are gallivanting off over El Norte and ruining their hopes of foreign support in their own local war, what does the other faction do?
 
If the Empire declares war we ally with the resistance and give them guns arms, and we fight a tired shot up force that has to fight through northern mexico. Post war the relationship between mexico and america will be in great shape. Their will be an agreement that it wasn't 'mexicos' fault nope totally the fault of those horrible evil invaders.

The relationship between France and america takes a nose dive for a generation.

If the resistance declares war they die, and get replaced by newer less stupid leadership, worst case senerio mexico loses more land as punsihment.
 
Could the Mexican Republic, before the European intervention declare war only to the Confederacy with the stated purpose of recovering Texas and looting money to pay its debts? That would give Mexico a credit extension so no French intervention while giving the US little power to do anything but complain.

And with its best armies and general in battle with the Federal armies Mexico would have a chance, won't they?
 
Could the Mexican Republic, before the European intervention declare war only to the Confederacy with the stated purpose of recovering Texas and looting money to pay its debts? That would give Mexico a credit extension so no French intervention while giving the US little power to do anything but complain.

And with its best armies and general in battle with the Federal armies Mexico would have a chance, won't they?

You really think the US wouldn't do anything about Mexico claiming they're invading to take what is still considered US territory?
 
What can they do? Most of the US Army is either facing the Confederate armies in the Eastern coast or east of the Mississippi. And their navy is fully invest in the blockade, isn't it?
 
That would give Mexico a credit extension so no French intervention while giving the US little power to do anything but complain.

First, France isn't giving more credit so Mexico can get into more debt.

Second, why does the US not respond? Texas is still American territory. It just happens to refuse to recognize that. The CSA would be hurt since Texan soldiers would have to stay home universally to defend against Mexican invasion as well.

And with its best armies and general in battle with the Federal armies Mexico would have a chance, won't they?

Nope. If they do well the US knocks them back across the border when the CSA is crushed.
 
What can Mexico possibly hope to accomplish by doing this? Whether the Union or Confederacy win, Mexico is getting curb stomped by somebody as soon as the Civil War ends. The day the war is over somebody's incredibly large and battle tested army is going to start marching south.

By invading Texas, Mexico has the dubious honor of angering both the USA and CSA in the middle of an all out war. If the CSA wins you'd probably still have Northerners volunteering to fight Mexico.
 
What can they do? Most of the US Army is either facing the Confederate armies in the Eastern coast or east of the Mississippi. And their navy is fully invest in the blockade, isn't it?

And the Rebs are gonna just sit there?

The US still Boarders republican Mexico, in case you forgot.

The New Mexico Theater gets murky as Everyone ends up fighting each other, but the Mexicans are going to be on the receiving end of things.
Neither side is going to be happy at the invasion, and the US can (theoretically) call up more troops for that front from the West coast.

In a war where one of the main goals was to keep the US together, they're not going to just hand over Texas because Mexico tried something stupid.
 
Wait, declaring war on both sides of an ongoing hostility? That's... just silly. If you rename the title "declares war on the Union or the Confederacy", then it might be reasonable; otherwise, ASB.
 
Top