Technological Advances:
Currently, significant investments are being made by private enterprises in driverless automobiles which can drive very safely on public roads. Google's own driverless car has famously more than a million miles without any accident that can be attributed to it; other companies are not far behind.
Furthermore, the field of robotics has come a long, long way - there's this famous dog type robot made by Boston Dynamics, for instance, which has demonstrated fairly sophisticated motor skills.
There's drones everywhere in the civilian sphere right now - and some of them have even made it to the white house undetected. And communication technologies have advanced to the point that it is possible that the drone sends back telemetry (including a high quality video feed) to a base station in another side of the planet. Further, miniature drones are rapidly becoming a thing.
We won't even talk about the famous swarm of micro-robots demonstrated on TED recently.
And all these devices have brains powered by sophisticated microprocessors which pack a serious punch even though they're sipping milliwatts.
Military Challenges
The world's most high profile military hotspot right now is arguably the middle east - with ominous rise of ISIS putting entire ethnicities (Shia, Kurds, Yezidis and Christians) in existential danger. ISIS is hard to beat because of apparent ethical qualms in the west (want to minimize civilian casualties - so ISIS can intermingle between the common folk and use them has human shields).
It is also hard to beat because the Iraqi armed forces aren't keen on fighting a war to defend something that they aren't particularly motivated to defend. The Sunni areas of Iraq are easy pickings for ISIS because of mutual mistrust among various sectarian factions.
America (one of the root causes of the conflict thanks to a historic blunder from W) is not likely to send any substantial number of troops because the public is against it now. Almost all discussion in the media is about sending people to "train Iraqi troops". (Apparently "I must fix what I broke" isn't a philosophy that applies to the mass media of nations at war.)
We'll use ISIS-motivated case study in the following section (primarily because if feels nice to have robots destroy creeps).
Putting it all together
Even right now, wars are no longer fought in battlefields between two opposing nation states. Most major conflicts these days are between state actors on one side and non state actors on the other. And the warfare is asymmetric; the non state actor usually has no qualms about disappearing into the general public after committing an act of war against the state actor. The state uses sophisticated missliles to neturalize these "terrorists" - often resulting in extensive collateral damage which results in negative PR and civilian casualties.
When a rich state battles insurgencies in the future, extensive utilization will be made of more granular unmanned reconnaissance (think of swarms drones or even insect sized robots) collecting detailed information to "confirm" the guilt of the party in question.
And it isn't exactly a stretch to expect that these little drones can be weaponized - thereby localizing these attacks to an extreme degree. (If civilians are able to do incredible stuff with their drone helicopters - a few orders of magnitude higher military budget can definitely put bombs on these things). I'd go even as far as suggest that these drones can be equipped with cyanide syringes to terminate the target with minimal damage to property (evidence) and civilian populace, thereby improving the PR impact of something like this.
It isn't as if these micro-drones will be the only line of defense against insurgencies. There will most definitely be self-driving tanks and ground troops - which will be completely immune to suicide bombings - because these things will be robotic - and will likely be controlled by a teenager sitting in his/her mom's shed in suburban dallas or something. The question of these devices falling into the wrong hands will also be moot - these things will just not have a way of being controlled without having access to the PC in Dallas. (The tank won't have a cabin, for example).
I expect that sooner or later technology will render all forms of terror moot - because hunting down and slaughtering terrorists will become an exercise with a zero human cost (albeit with a finite cost in machinery, but 3d printing is making machinery cheap anyway). This will render the world bi-polar with America on one side and China on the other. But I expect an equilibrium with complete peace and mutual distrust.