As others have said Larry, be sure to check all your options before purchasing. Alienware is a decent brand, but nowadays unless you go to a bargain basement company, there are many companies of good repute that use good components in their system builds, and many offer financing as well. Just post here if you have questions, some companies will cheap out on components, many here can spot that and suggest the who/what/where/etc about good options.
What state are you in Larry, there are frequently good companies that build gaming PCs and offer everything you're looking for, and will in most cases be cheaper than big brand names like Alienware for example, a company whose once big "advantage" no longer exists.
So far as your overall components, yes, an i5 8600k with a 1080 will get you back into this game at mostly, if not across the board, max settings. The 8600ks are usually good overclockers, and the 1080 can be overclocked reliably as well, so you'll be able to gain a fair bit of extra performance due to you buying the "k" variant of the 8600 chip. Once you've settled on a build, post here about that and lots can help you out of you wish to go down that road (it's quite safe these days with proper cooling, a mild overclock is easy to do, and worth it IMO for the bang/etc ratio you get out of that, but again, that's something to concern yourself with once you have your system in hand and up and running).
One thing I'll suggest you consider - your LCD monitor, IMO getting a 144hz LCD will have a huge effect on your gaming experience in AH3 - everything else too - and you can get a really good 24 or even 27" (higher even if you need or want it) 144hz monitor for not a huge pile of $. Be sure to factor this into your budget, at least IMO. I've recently seen Asus 24" 144hz lcds for sale for $250 USD, and have seen re-certified ones with a year warranty for under 200 bucks, so again, be sure to consider this Larry - ask anyone with a 144hz (or better) lcd, not one will say they wish they hadn't got it, and then some.
Keep posting if you haven't purchased already, lots of players here are invested into the hardware side of things with AH3 as it pertains to the players - getting the best possible deal and equipment they can - even more so for a good guy returning to the game.