The S-400 missile system may be one of the most lethal anti-aircraft missile systems currently deployed. The S-400 system was developed by the Russians and is used by the Russian Armed Forces. As of 2017, the S-400 system was considered one of the most effective air-defense systems ever created.
The system has four missiles and can be used in short-range, medium-range, or long-range. It has excellent targeting capacity, and anti-stealth capabilities.
The Mother of All Bombs (MOAB) may be considered an alternative to tactical nuclear weapons, but it is not a perfect solution. It is true that the MOAB may cause fewer civilian causualities but it is not a guarantee. The MOAB was dropped in Afghanistan in April 2017.
The Afghan army said there were no civilian casualities, however there were conflicting reports that at least two civilians were killed in this attack. The MOAB may be a slightly better alternative to nuclear weapons, but it is by no means the best solution.
The F16 Fulcrum is definitely a versatile and effective combat jet. Because it was designed and built in the US, it is different from other combat jets and based on your question, we cannot compare jets built outside the US.
There are plenty of effective and versatile combat jets that are built outside of the United States. I would bet that the F16 Fulcrum would be among the best combat jets in the world but I would not confidently say that there are no combat jets that are more effective.
The Germans liked to act like they had superior weaponry over the Allies in World War II but in reality, the Germans‘ weapons were less powerful and accurate than the Allies. The Allies has more powerful and better weapons, but more importantly, the Allies forces had momentum, as more and more, allies joined hands against the Germans.
The Allies also had superior intelligence gathering compared to the Germans. The Germans were more willing to spare innocent lives, which made them a difficult enemy.
A nuclear warhead is different than nuclear weapon. A nuclear warhead specifically refers to the toxic materials or the explosive that comes from a missile, torpedo or rocket while a nuclear weapon refers to the main explosive device that causes nuclear reactions. A warhead can either be explosive, chemical and biological.
Explosive warhead can damage the surrounding areas with a blast and completely disintegrate the main target, the chemical warhead is used to kill human beings through a toxic chemical such as nerve gas or poison gas, and a biological warhead is a type of infectious agent that can either make people sick or ultimately kill them. The nuclear warhead is the bullet-shaped canister found on a missile, torpedo or a rocket.