While Lincoln was a great leader, I just don’t see him as an empire builder. The great push for the settlement of the west was spurred on as early as the Monroe presidency.

Lincoln roped in the territories to gain support for the abolitionist movement and to deny the south any additional support for their secession.

So yes I agree Lincoln was a great President, but not so much a driving force for American Imperialism.

Now if you want for someone in that general time period you need not look any further than Rutherford B. Hayes. This was the cat that told Columbia “Nice canal you got there, I think I’ll take it. Thank you.”