They could have, but like most of the country, nobody wanted it. They thought it was a waste of money. It was labeled Seward's Follies. But William Seward got it pushed through and President Johnson signed it in 1859.
Now it's given us more oil than Texas, more gold than California, more timber than Washington & Oregon, more seafood than all the other coastal states combined and more TICE than anyone knew possible.
It also gave us Sarah Palin, so doing the math we still come out ahead, but just barely.