1. Cured (traditional) - Cured meat in the traditional sense basically means covering it in salt and letting it age. You can either brine it or dry-salt it. No nitrates/nitrites. Cured bacon in this sense would mean taking the whole slab of bacon, covering it in salt, and hanging it to dry - "dry-cured". This yields unique flavor and, more importantly, greatly extends shelf-life. Prosciutto and jamon are made this way and can be kept for years with this method.
2. Cured (USDA definition) - Cured per USDA means injected with a salt and nitrate/nitrite solution. Sometimes spices are added. Products like bacon are typically kept wet and sealed in plastic, though some things are dry-aged, as above. This yields mild visual, flavor, and moderate shelf-life improvements to the product. What most Americans know as ham ("city-ham") is processed in this way, as opposed to country ham, which is traditionally-cured, like prosciutto.
3. Uncured (USDA definition) - Uncured per USDA differs from USDA-cured only in the source of the nitrates/nitrites. In this method, they typically come from celery salt. As with USDA-cured, this gives mild visual, flavor, and only moderate shelf-life improvements to the meat.
Most Americans have never had traditionally-cured meat. Traditionally-cured meat doesn't have anything like the harmful effects of USDA-cured/uncured meat does, due to the absence of nitrates/nitrites. I would also wager that a wet, fatty, acidic thing marinating inside plastic packaging also has something to do with being cancer-causing, as it likely leeches chemicals from the plastic.
So traditionally-cured meat is what you want. Salt-only. Unfortunately, it's harder to find in America. And if you do, it's priced like some kind of gourmet luxury good - unacceptable. Cured meat is how my peasant family got through winters in days past - it's for everyone, not just kings!