Russia's invasion of Georgia strikes at the heart of western values and our 21st-century system of security. If the international community allows Russia to crush our democratic, independent state, it will be giving carte blanche to authoritarian governments everywhere. Russia intends to destroy not just a country, but an idea.

For too long we underestimated the ruthlessness of the regime in Moscow. Within 24 hours of agreeing to a ceasefire, Russia's forces were rampaging through Gori; blocking the port of Poti; sinking Georgian vessels; and - worst of all - brutally purging Georgian villages in South Ossetia. The Russian leadership cannot be trusted - and this hard reality should guide the west's response. Only western peacekeepers can end the war.

Russia also seeks to destroy our economy and is bombing factories, ports and other vital sites. Accordingly, we need to establish a modern version of the Berlin airlift. The United Nations, the US, Canada and others are moving in this direction, for which we are deeply grateful.

As we consider what to do next, understanding Moscow's goals is critical. It aims to satisfy its imperialist ambitions, to erase one of the few democratic, law-governed states in its vicinity - and, above all, to demolish the post-cold war system of international relations in Europe. It is showing that it can do as it pleases.

The historical parallels are stark: Russia's war on Georgia echoes events in Finland in 1939, Hungary in 1956 and Czechoslovakia in 1968. Perhaps this is why so many eastern European countries, which suffered under Soviet occupation, have voiced their support for us. Russia's leaders see us as a threat because Georgia is a free country whose people have elected to integrate into the Euro-Atlantic community. But Russia's rulers do not want their nation or its borders contaminated by democratic ideas.

Since our democratic government came to power after the 2003 Rose revolution, Russia has used economic embargoes and closed borders to isolate us, and has illegally deported thousands of Georgians. It has tried to destabilise us politically with the help of criminal oligarchs. It has tried to freeze us into submission by blowing up vital gas pipelines in midwinter. When all that failed to shake the Georgian people's resolve, Russia invaded.

Last week Russia, using its separatist proxies, attacked several peaceful, Georgian-controlled villages in South Ossetia. On August 6, just hours after a senior Georgian official travelled to South Ossetia to attempt negotiations, a massive assault was launched on Georgian settlements. Even as we came under attack, I declared a unilateral ceasefire in the hope of avoiding escalation, and announced our willingness to talk to the separatists by any means.

But we then learned that columns of Russian tanks and troops had crossed Georgia's sovereign borders. The thousands of troops, tanks and artillery massed on our border are evidence of how long Russia had been planning this aggression. Our government had no choice but to protect the country from invasion, secure our citizens and stop the bloodshed.

For years Georgia has been proposing 21st-century, European solutions for South Ossetia, including full autonomy guaranteed by the international community. Russia has responded with crude, 19th-century methods.

It is true that Russian power could overwhelm our small country - though even we did not anticipate the ferocity and scale of Moscow's response. However, we had to try to protect our people: any democratic country would have done the same.

Facing this brutal invading army, our government decided to withdraw from South Ossetia, declare a ceasefire and seek negotiations. However repeated attempts to contact senior Russian leaders were rebuffed. Russia's foreign ministry even denied receiving our notice of ceasefire hours after it was officially - and very publicly - delivered. This was just one of many cynical ploys to deceive the world and justify further attacks.

This war threatens not only Georgia but security and liberty around the world. If the international community fails to take a resolute stand, it will sound the death knell for the spread of freedom and democracy everywhere. Georgia's only fault in this crisis is its wish to be an independent, free and democratic country. What would western nations do if they were punished for the same aspiration?

I have staked my country's fate on the west's rhetoric about democracy and liberty. As Georgians come under attack, we must ask: if the west is not with us, who is it with? If the line is not drawn now, when will it be drawn? We cannot allow Georgia to become the first victim of a new world order as imagined by Moscow.

· Mikheil Saakashvili is the president of Georgia

© Washington Post