My primary difficulties at Deity level (and really all the levels) is that I have not gotten the hang of diplomacy. That is to say that I have never been able to stay out of wars. I do not antagonize the AI's and generally stay out of the way, and will give them advances when they ask for tribute, but this does not help. They always come after me by the 1700's or 1800's.

I can pretty easily outstrip the other AI's tech advances but inevitably I am attacked on all sides. I can handle the multi-front conventional wars until an AI builds Manhatten Project, and starts nuking me. I am usually not fast enough to build a space ship or negate the AI's before this happens.

So my question is two-fold. First, what does it take to peacefully build your spaceship short of reducing all the AI's to rubble. Give away more? Build more military and put them on AI's continents? What? Also, has anyone ever gotten a significant peace bonus in their CIV score?

Second, if appeasement does not work, what is the best way to handle the nuclear threat other than getting to laser before Mahattan project is built and quickly (and expensively) building SDI in all cities. Is there a way to convince a nuclear power that you are superior to in every other way to hold off on the nukes while you get your SDI's in place? Or should I just make sure that I have more nukes than the AI's and retaliate in kind?

As a last question, is there an option to just cut out nuclear war?

Buying or building SDI in all of your cities is expensive and time consuming... try to avoid that option.

Two other things you can do -

1) If you have established embassies with the other civs you can check intelligence on them and click on the cities box at the lower left - it will tell you what Wonders are being built. If a Civ is building the Project then get a spy or dip over there and sabotage it. (An out of the way airbase, with a stacked dip and caravan that connects to a civ's rail network will frequently go unnoticed if you want to set it up early.)

But there are things you can do. Sten's suggestion is one good one: track Wonder-building and sabotage it. I was surprised to find how easy that can be; I've succeeded twice in two tries, selectively sabotaging Wonder production.

You can also capture the city that's building the Wonder, either by inciting revolt or by military force. Again, a key is knowing where it is.

Also, you don't necessarily have to put SDI into every city to protect them all. I only figured this out because a couple of times the AI nuked my cities that had no SDI, but I'd get the "protected by SDI" message. Finally I checked the rules and realized that SDI protects everything within three squares, and that includes OTHER CITIES within three squares. If your cities are close together, you can make one SDI protect several cities. If they're not, then you can build a strategic late-game city for no purpose except to build an SDI that will protect 3-4 neighboring cities. The fun part of this is that the AI will crank all of its production into nukes and blast away over and over at the same city, because as always, it cheats and knows there's no SDI there, but it doesn't learn that it's protected anyway.

If you've got a big empire, many of your cities will be out of range of land-based nukes, and I don't think I've seen the AI use a sub-based nuke on me yet, so those interior cities may not need protection at all.

Finally, there's the airbase cheat: build a line of adjacent airbases between you and the bad guys, and any missiles trying to cross the line will land and you can toast 'em.

On capturing the city building the wonder. You usually don't even have to capture it. If you can knock off some of the defenders, the AI will usually shift production to a defensive unit. I love killing 250 shield rifleman.

Or if you use the SUPER DEFENSIVE POSITION strategy, (fortress on a mountain in range of one of their cities) the AI will forgo building anything but offensive units.

But having said that, like previously posted, I'm usually so far ahead that I have SDIs built long before the AI can build nukes.

MP games are something else.

I would note that from what I have seen the AI's range on the nuclear missiles is unlimited. They have nuked cities deep in my heartland while I have the surrounding oceans swarming with helicopters and fighters to the extent I am positive that there are no subs lurking out there. I would also note that I never see where the nukes are coming from, they just appear next to the city. All this would make it seemingly impossible to build an airbase maginot line from my point of view (also I rarely share a contintent with other civs at this point.

I can empathize with your problem as I suffered the same fate in my attempt at OCC12, which happened because I wasn't sufficiently ahead in the tech race with the added Fundamentalist handicap.