To do this, you need near-ish bases. Canada is indefensible and the West Coast puts you on the wrong side of the Rockies, so that means the Caribbean. Florida is poor invading country, like most of the coast from the Virginia Capes around to the Mississippi Delta, so I'm looking to Texas.
In turn, that means air bases in Mexico or the Yucatan. It's unlikely the Mexicans will let us in peacefully, so we need to seize the bases. In fact, we need to fight our way past Cuba to get there. We probably need to invade Cuba and maybe southern Florida to do this, and credibly threaten the north-east to avoid a concentration of forces. At some point, this involves crossing the Atlantic, then defeating the US Atlantic Fleet.
Assuming we pull this off, first objective ashore is Houston. This will be our logistic hub. Then we're aiming to advance up a Dallas-Oklahoma City-St Louis-Chicago axis, cutting the US in two, before wheeling right up the Ohio valley. This is a scheme on a par with Barbarossa, with lines of supply almost on a par with the Pacific. Several of the shaping operations would rank as the greatest military operation of all time. Opportunities for catastrophic failure are numerous.
The alternative is to push down from Alaska, but that's a lot of miles of absolutely nothing that you have to fight through before capturing anything of value.