In a New Scientist Special Report titled 'Instant Expert: Weapons Technology'
'Violence and conflict have been a feature of human life throughout history. Starting with simple weapons, people have developed ever more advanced methods to kill one another. Technology has dominated warfare since the early 1900s, and an astounding 190 million people may have been killed during the 25 biggest conflicts of the 20th century.
Today guided weapons, like "smart" bombs dropped by stealth bombers, coupled with space-based sensors and precision satellite navigation, provide decisive advantages in conventional warfare. In this high-spending game, less capable opponents are soon reduced to guerrilla tactics, and human cost of war remains high.
The US has embraced Full Spectrum Dominance, the belief that superior technology in all fields guarantees victory, though critics disagree. This has led to ever more sophisticated and expensive aircraft and a proliferation of unmanned systems, including robot aircraft to attack targets. Future plans may include swarms of flying robots, while an existing desert race for driverless vehicles may pave the way for autonomous supply vehicles.'
You can read more at the above link.