>>715175376
A single bomber at high altitude facing numerous radar/strategic SAM sites, is dead meat. There's just no getting around that, that's kind of how nuclear bombs are balanced in this game.
At least in singleplayer scenarios, you basically have to fly non-nuclear attack craft to clear out those radar sites and long-range SAM sites with tactical strikes, to clear a path for your eventual nuke run. In MP (at least, in PVE MP) I assume this is easier because you can have other players running around knocking out the air defenses (SEAD work) and even goading those long-range launchers to target them, before ducking behind hills.
Also, for radar guided missiles generally, you want to do two things: the first is called notching, and that's when you orient your plane so you're flying perpendicular to the radar-source. This makes it harder for the missile to "see" your plane, because you're not moving towards or away from them and therefore have a reduced radar signature.
The second thing you want to do is use that ECM buttom the game gives you, specifically when you're notching. You want to do this for long enough that the missile loses lock.
But frankly, when you're talking about taking a strategic bomber, there's nothing you're going to be able to do to outwit multiple long-range radar SAM sites other than staying off their radar entirely. The best defense against those kinds of missiles is honestly masking yourself with terrain at low altitude.