It is important to note in the matter of international relations, actions of other nations can affect how something is perceived at home, even though the conditions and ground situation is very different. This is because interested parties use precedent to their advantage, no matter the rights and wrongs of that action.
With Ukraine which was in the Russian orbit, now through an internal insurrection, deposed their Russian financed front man. They now want more independence from the Russian Influence, but it is proving a little difficult, as the both the Russian warm water port in Crimea on the Black Sea is home to a large Naval Base, which the Russians want to keep at all cost, and the majority of the people in Crimea are Russian or Russian speakers, along with a sprinkling of Muslim Tartars of the famed horseman of yore.
Putin is hoping that the referendum on Sunday in Crimea to secede will go his way, as it obviously will due to the overwhelming pro Russian and Russian speaking majority in that state. IF they secede and it is recognized by the world, it will be a disaster for the SL Govt. as it will create a precedent for Tamil separatism demands, even though both India and Sri Lanka are against that!
THE US has put pressure on the Russians to leave Crimea alone, and not interfere in Ukraine, and have threatened Russia with sanctions which despite the overwhelming size of the Economy will nevertheless be felt amongst its citizens despite their oil and gas reserves. The Russians still need western technology and don’t want to upset the apple cart, and Obama is hoping that Putin will see sense, but don’t count of it due to his Soviet mentality of a KGB agent which has still not left him.
Without Crimea, Ukraine will NEVER return to the Russian Orbit and would more likely want to join NATO, and now there is an excuse to do so for security reason, so Obama is counting on that eventuality to stop Putin from annexing Crimea. Only time will tell what happens, but the fact that Putin is sending troops into Crimea in mufti, means he wants to be ready for a quick exit if the need arises, and is not intent on showing a Russian takeover as yet.
Sri Lanka would do best to learn from this experience, that balancing a level of autonomy within the Unitary state, will prevent separatist tendencies and a good rapport with India will put paid to any rumblings of separatism which will be forcefully cast off by any Indian Govt. even the Modi Govt. expected later on.