Update!
Oh Those Troublesome Whigs
The news of Taylor’s failure to take Tampico, and the hasty advance of the Mexican army, and the Foreign Legion, towards the border caused an uproar within the halls of Washington D.C. In response to the prolonged war the Whig Party had voted on a resolution, that while it praised the valor, and skill of the men fighting, it added a clause stating that the war had been
“unnecessarily and unconstitutionally begun by the President of the United States”. Abraham Lincoln, a young and fiery Whig, rose to defend the Whig vote by adding,
“Allowing the President to invade a neighboring nation, whenever he shall deem it necessary, would place the President where kings have always stood.”
Lincoln challenged President Polk to
“establish whether the particular spot on which the blood of our citizens was so shed was or was not at the time on our soil. Let the President answer fully, and candidly, with facts and not with arguments. Let him remember he sits where Washington sat, and so remembering, let him answer as Washington would answer.” The young congressman concluded
“Again, it is a singular omission in this message, that it, no where intimates when the President expects the war to terminate.” [1]
However the Democratic Party, and the supporters of the war, most whom hailed from the South, held that the war was being fought to secure territory that was justly American. However, this same argument provoked the Northern Democrats who felt cheated out by the Oregon Treaty. Led by John Van Buren, the son of the former President Martin Van Buren (and endorsed by the elderly President), the Northern Democrats also called for a hasty end to the war.
With the election of 1848 approaching, Polk opted to send Nicholas Trist to negotiate a peace with the Mexicans. Trist was given a particularly vague set of instructions urging him to only accept terms that respected all the territory that was rightfully American and/or securely in American hands. For an ardent expansionist like Robert J. Walker, this could have meant anything north of the 26th parallel [2], for a Whig like Lincoln could have meant only the territory that the Mexicans had recognized as part of Texas.
Trist arrived in Veracruz early in March of 1848 [3] and made his way through the American occupied central Mexico to Cuernavaca, where General Scott had camped out for an upcoming siege of the Mexico City Valley.
With the election of 1848 approaching, Polk opted to send Nicholas Trist, to negotiate acceptable terms with the Mexicans.
So how was the war going on exactly?
Before Scott had marched towards Cuernavaca from Puebla, reinforcement had arrived under the command of Giddeon Pillow. From puebla Scott was leading an army of 12,000 men towards the Mexico City Valley. Meanwhile Generals José María Yáñes and José de Urrea lead a force well over twice the size, mostly made up of last minute volunteers. Marshy ground and mountainous terrain had made the American advance slow and cumbersome, but the trek between Puebla and Cuernavaca had been relatively free of engagements besides a skirmish against Joaquín Rea’s militia alongside the Iztaccihuatl pass that, although an American victory, had forced Scott to approach Mexico City from the south via Cuernavaca.
On March 18th, 1848 Scott led the American army into the valley of Mexico, the resulting Battle of Milpa Alta, was the bloodiest in the war. Scott was not only facing the Mexican army under Urrea and Yáñes, but a last minute volunteer force of Mexico City’s residents led by President Herrera. This was the only battle President Herrera was present in. In the end both sides claimed a victory. The Mexican army had stopped Scott from advancing into Churubusco and possibly Mexico City itself, while Scott had managed to set his foot inside the Mexico City Valley. However, the losses of suffered on the American side prevented him from pressing forward. Thus Scott had no difficulty accepting a temporary armistice when President Herrera offered his terms for peace.
Herrera’s terms recognized the United States’ sovereignty over Texas, but established the border at the Nueces and Pecos Rivers, respecting the established jurisdiction of the Mexican departments of Tmaulipas, Coahuila, and Chihuahua. Form the source of the Pecos River [4]; the border would follow a straight line up to the 37th parallel and a straight line westwards towards the Pacific Ocean. This border would have placed; the much sought after, San Francisco Bay in American hands but would have kept Monterrey Bay within Mexico. [5]
General Scott however had problems with these demands. His army lay at the doorstep of Mexico City; even if Taylor was pushed back to the Bravo he was certain that the occupation of Mexico City would force the Mexicans to secede the whole of the territory in question. Furthermore, Trist took a more extreme approach to his instructions, and insisted that he had not been authorized to accept such terms.
With the arrival of Giddeon Pillow’s reinforcements Scott opted to wait out the short armistice and continue onto Mexico City. However, when Pillow’s troops arrived in Puebla something unexpected happened… and Winfield Scott was trapped within Mexico with no supply line.
[1] This is a paraphrase of the actual speech Lincoln gave condemning the war.
[2] This would basically include all the northern Mexican provinces usually seen annexed in most Ameri-wanks.
[3] This is happening after Taylor is defeated in Tampico but before he looses his hold of Victoria.
[1] A bit north of OTL’s Roswell, NM.
[5] Herrera had actually presented a very similar proposal to the Mexican Congress at the start of the war in OTL. After the Battle of Churubusco Santa Anna once again offered these terms to Scott, who like in TTL refused to accept.