The answer is both yes and no, in my view. Yes, we can purge terrorist organizations in various ways to render them ineffective and an essential non-issue. However, it is impossible to ever completely eradicate terrorism as it is a tactic that has been used throughout time. There is no way to combat that, only making it less prevalent in today's society.
As I have said in this thread once before (sake of time here), I believe a three-pronged approach is the best method to take in regards to a comprehensive strategy to combat terrorism. I must warn you, this may be a wall.
This is why combatting terrorism is a three-pronged attack: politically, economically, and militarily.
A large reason as to why terrorism happens is because of political disadvantages to minorities or an otherwise corrupt government. Large-scale political reforms meant to lower hostilities (be it for political or sectarian reasons) is needed. It could be argued a fourth prong could be added, but I like to add social issues into the political prong because they're closely related. Improving social conditions, like education, healthcare, disenfranchisement of minorities, etc., would also be beneficial to mitigating the chances of political violence.
Focusing on education here, this includes both religious and secular education. Working with mainstream Muslims and Islamic scholars to help change the way in which Islam is taught to the masses in "problem areas" is something that should be heavily encouraged. Reformation of radical madrasas throughout the Muslim-world would definitely help in lowering the rates of Islamic terrorism. Promoting secular-education--this means like a Western-style education--would also be beneficial. Obviously, the latter is much harder to accomplish due in part to the cultures of these areas, but the former is already happening.
Another reason is the large amount of poverty in many of the places that face a large terrorism threat. Helping to improve economical conditions in various countries and/or regions would also be beneficial. We, being the international community, could help by building capacities for improved infrastructure to vastly improve trading routes, thereby adding jobs to the local economy. Providing work in many other ways can, should be, and is being done. Helping the economies of these countries would be directly tied into better internal improvements.
The third, militarily, is the most axiomatic. You can't fully destroy an enemy without literally destroying them; so I'm not going to waste my time to make a detailed case here. Although, I will say building partnership capacities are pretty instrumental when and if done correctly and the partner countries are allocated the needed equipment and supplies. Insurgencies are better won by local forces than outside powers; however, this isn't to say we should sit back and let under-equipped and under-trained partner states deal these issues. Rather, like I implied above, we should be incredibly instrumental in providing intelligence support and sharing, logistical support, training, and if need be, direct military support short of full-scale intervention.
To quote myself from an essay I did for school:
[quote]I would like to use Somalia as an example. Somalia just recently achieved a huge milestone of electing a President; as a result, this is improving the lives of their citizens. With this huge political achievement, they are now re-establishing political ties, gaining more assistance from different countries. Then, the UN Arms Embargo on Somalia has been lifted for a year. This will allow countries, like the US, to send weapons to the Somalian military to fight back al-Shabaab, themselves. Along with the political achievement, the economy of Somalia has been improving since this new government came into place. Thanks to reconstruction in the country, markets are opening back up, natural resources in Somalia are finally being utilized, and so on and so forth. With this economic growth, hopefully the general populace can finally get better living conditions. The last prong, militarily, has already been underway since 2007. The African Union forces (along with Ethiopian forces and US assistance) have done a great job of pushing al-Shabaab out of places like Kismayo, Mogadishu and Merca. Now that the US has authorized military aid to Somalia, this trend of pushing back Islamic militants will presumably continue. The end result of this approach is that terrorism becomes a non-issue, like how it is for the United Kingdom since the Irish Republican Army (IRA) is no longer a problem for them.[/quote]
While Somalia still has a ways to go in terms of eradicating Shabaab from being such a menace, they have made considerable improvements in the last few years. Just the last week, they even made more military advancements in regards to pushing Shabaab out of several key towns. Now, the question is: How long will they keep Shabaab out of these towns? This has yet to be seen and in the past, towns that have been captured from Shabaab were quickly recaptured. Hopefully, this does not happen this go-around and the AU forces continue to make advancements.
Politically speaking, they now have a semi-working government in Mogadishu. This, obviously, does wonders for a country that has been war-ridden for the past two decades. There are reports going around recently that Somalia and Somiliand are close to an agreement to improve relations between the two entities. This will provide each territory with extra resources, including oil and natural gas. Assuming these two can realign as one entity, this would provide Somalia with some much needed economic prosperity vis a vis profits from oil exports. So, while things still need to be done and accomplished in Somalia, it's not all dark and gloomy.
But Somalia isn't just the only example how a state can bounce back (or at least try to anyway) from the problems of terrorism. The UK, Turkey, and one could even argue Tunisia as being successful in this respect. Obviously, in both Turkey and Tunisia there is still work to be done, but terrorism is not as large of an issue as it was once. Morocco is also a country that has been hailed as being a success story as to how terrorism can be downtrodden in a country.