The US didn't have such ambitions so far abroad? Hmmm, that's strange I seem to remember hearing about marines in Tripoli less than 10 years after the Constitution is ratified... The Monroe Doctrine, while remembered as having been a giant middle finger to Europe telling them to stay off the Americas was actually about Monroe saying "eh, I know a LOT of Americans want the USA involved in Greek independence from the Turks... however, I'm going to say we won't get involved in Europe in exchange for Europe staying out of America, because our Turkey got us what we needed for our trade with China", we came very close to getting involved in Greek independence back in the 1820s.
America, despite the myth of isolationism being the standard prior to WWII it is isolationism that has been the exception rather than the rule. Remember that many individuals, including slave owners, got involved with the American Colonization Society to found Liberia. Even Ulysses S. Grant as president attempted to annex the Dominican Republic to create a US state that Blacks could be the dominate race in. While this isn't the same as given how few Jews lived in the USA compared to race relations between whites and blacks in this period it does give precedent for it being plausible for Lincoln to give moral support to some NGO to form, a proto-Zionist movement.
Perhaps we can see an American version of the Uganda plan that Britain puts forth later on, or an attempt to settle Jews in some part of the west so they can become a majority and have a Jewish majority US state (and therefore 2 Senators and at least 3 electoral votes). When dividing New Mexico and Arizona it wasn't, as some claim, the fact the Confederacy dividing it on a east-west line that caused the US Congress to divide it by a north-south line to be different... it was because New Mexico as opposed to Arizona has a LARGE plurality (almost majority) Hispanic population and the point was to give them their own state. Utah took so long to become a state and states that shouldn't have been, like Nevada, were formed to limit the Mormons to a state of their own just barely encompassing where Mormons were a majority. So there is some similarity to what the US Congress did in OTL regarding minorities. Not much of a retroactive precedent but does make it less than ASB that the US attempts (unsuccessfully?) to pull off an American version of what the Soviet Union would attempt to do in Siberia with a Jewish Autonomous Oblast.