I think that Cambodia could have the potential to become a regional power in the SE region.
Firstly, Every existing country in Mainland Southeast Asia or Indochina Peninsula has ever been a regional power in the SE for at least, some periods of their history. Only in a few recent hundred years, Vietnam and also Thailand has become the strongest power in Mainland Southeast Asia but looking back further, about recent 1000 years, Cambodia and Myanmar were really true regional powers.
Of course, nothing lasts forever – The rise and fall of each empire in the SE region have their own reason. However, each existing country today have their own period which has/had ever shadowed on the Mainland SE region and No-one make sure that they will never recover back in one way or another way. So, I think that Cambodia is no exception. As I remember that during the peak of the Cambodian Angkor Empire, they had covered up most of Thailand, Laos, and part of Vietnam today. Also, interestingly, they had waged many invasion wars to conquer the Daiviet Kingdom (the predecessor of Vietnam today) many times. Of course, today, Cambodia could not come back to the Angkor period by invading its neighbors but the Cambodians have the great legacy and also the glorious treasures of their history to rebuild their country to become Great Cambodia Again.
As all, you know that Cambodia is 181.000 Km2 in areas which is larger much compared to 100.000 Km2 of South Korea, 20.000 Km2 of Isreal. Most of the Cambodian territory is flat with most of the fertile farming land that could feed larger population and also provide resources for the development of Cambodia.
So, from my view, Cambodia has enough potential to become the regional power in the SE region. One of the possible ways is to form the Union of the ASEAN that is a kind of another the European Union where all of the countries are equal in making decisions and also contributing equally to the peace, stability, and prosperity in the SE region. There will be no need for Cambodia to wage invasion wars against its neighbors or challenge others of the regional powers in the SE to secure its Cambodian role as the regional power.
To do it, Cambodia should not only develop itself but also become a responsible members instead of doing something badly to the unity of the Asean as what happened in 2012.
Source: quora.com