At the beginning of 1864 an advance from Chattanooga southward into the heart of the Confederate country was in contemplation. Grant and Farragut wished that it should be supported by a joint military and naval attack upon Mobile, in Alabama, on the Gulf of Mexico. Other considerations on the part of the Government prevented this. In 1863 Marshal Bazaine had invaded Mexico to set up Louis Napoleon's ill-fated client the Archduke Maximilian as Emperor. As the so-called "Monroe Doctrine" (really attributable to the teaching of Hamilton and the action of John Quincy Adams, who was Secretary of State under President Monroe) declared, such an extension of European influence, more especially dynastic influence, on the American continent was highly unacceptable to the United States. Many in the North were much excited, so much so that during 1864 a preposterous resolution, which meant, if anything, war with France, was passed on the motion of one Henry Winter Davis. It was of course the business of Lincoln and of Seward, now moulded to his views, to avoid this disaster, and yet, with such dignity as the situation allowed, keep the French Government aware of the enmity which they might one day incur. They did this. But they apprehended that the French, with a footing for the moment in Mexico, had designs on Texas; and thus, though the Southern forces in Texas were cut off from the rest of the Confederacy and there was no haste for subduing them, it was thought expedient, with an eye on France, to assert the interest of the Union in Texas. General Banks, in Louisiana, was sent to Texas with the forces which would otherwise have been sent to Mobile. His various endeavours ended in May, 1864, with the serious defeat of an expedition up the Red River. This defeat gave great annoyance to the North and made an end of Banks' reputation. It might conceivably have had a calamitous sequel in the capture by the South of Admiral Porter's river flotilla, which accompanied Banks, and the consequent undoing of the conquest of the Mississippi. As it was it wasted much force. Before Grant could safely launch his forces southward from Chattanooga against Johnston, it was necessary to deal in some way with the Confederate force still at large in Mississippi. Grant determined to do this by the destruction of the railway system by which alone it could move eastward. For this purpose he left Thomas to hold Chattanooga, while Sherman was sent to Meridian, the chief railway centre in the Southern part of Mississippi. In February Sherman arrived there, and, though a subsidiary force, sent from Memphis on a similar but less important errand somewhat further north, met with a severe repulse, he was able unmolested to do such damage to the lines around Meridian as to secure Grant's purpose.