Why didn't Romania join the invasion of Czechoslovakia of 1968?

As the Soviet Union worked tirelessly to keep the Iron Curtain up and strong after the Second World War, Czechoslovakia became a threat to this objective. As a satellite state of the Union, Czechoslovakia was meant to remain a firm communist-led country, just like the rest of the Eastern Bloc. So when a new Czech government began a process of reform known as the Prague Spring, the Soviet Union quickly became concerned. In hopes of quelling these liberating reform efforts, the Soviets reached out to their Warsaw Pact allies to plan an invasion into Czechoslovakia and intervene. Poland, Bulgaria, East Germany and Hungary subsequently threw their support behind this Soviet plan. But two nations refused to do so. Both Albania and Romania were unwilling to join the invasion, and Romania's Nikolai Ceausescu went out of his way to condemn the operation. So what made Romania so unwilling to join the Warsaw Pact invasion of Czechoslovakia? First, let's rewind so we can understand what really happened in the Czechoslovakia-Prague Spring. When Alexander Dubčák succeeded Antonín Novotný as the first secretary of the Communist Party of Czechoslovakia on January 5th, 1968, one of his main goals was to continue a process of liberalization reforms that had slowly begun. He quickly began to rectify previous policies to allow for more freedoms and less censorship, and wanted to establish a state run by socialism with a human face. After only a few months, Dubčák had revised the constitution in favor of more civil rights, started a rehabilitation process for political dissidents during the Stalin era, and was working toward democratizing the government at the request of the people. These reforms were proving successful, and this time of newfound freedoms became known as the Dubčák was highly confident in his ability to continue these sweeping changes whilst maintaining stability and a socialist state, but the Soviet Union was not so sure. The drastic shift in Czechoslovakia's structure set off alarm bells for the Soviets and even some of their other satellite states. What would this mean for communism as a whole, and how would this affect the Soviet dominance throughout the Eastern Bloc? Well, according to the Soviets, the effect would be negative, and therefore must be prevented. Negotiations were first attempted between Czechoslovakia and the Soviet Union as the latter hoped to push the former back into what they deemed to be the right direction. These negotiations unfortunately failed, though, and the Soviets were forced to come to an alternative conclusion. With the 1956 Hungary uprising still fresh in the mind of Moscow, it seemed like the only option would be to crush a possible revolution before it could even begin. Almost ready to take action, the Soviets now reached out to some of their fellow Warsaw Pact allies to recruit support for their intervention to give a message of unity. The Warsaw Pact was a defense treaty that had been formed by the Soviet Union, East Germany, Hungary, Poland, Romania, and actually Czechoslovakia as well. Much to the pleasure of the eager Soviets, four of these nations decided to join the cause and more or less bully their wavering ally into complying with the rest of the pact once again. Bulgaria, East Germany, Hungary, and Poland were now at the ready to intervene on behalf of the Soviet Union and the Communist Bloc as a whole, but Albania and Romania were less willing. Albania was already at odds with the Soviet Union over political disagreements and relating to the Soviet Union's post-Stalin changes. When the rest of the Eastern Bloc began to discuss an invasion of Czechoslovakia to intervene with their politics, which the Soviets may have also wanted to do to Albania after the latter turned down suggestions for policy changes, Albania hit its breaking point with all of the Warsaw states. Enough was enough, and with the escalation of tensions, Albania formally withdrew from the Warsaw Pact in September of 1968. Romania was the other country that refused to participate in this planned invasion, and was definitely not subtle about its opposition either. The Socialist Republic of had been no more friendly with the Soviets than the Albanians were as of recent times, and their leader Ceaușescu had already voiced his support for the freedoms of Czechoslovakia. After declining to join his nation's allies for the invasion of Czechoslovakia, Romania's leader took his opinions public in Bucharest. Giving a speech to 100,000 Romanian people in the Palace Square, he condemned the actions of the calling the invasion plan a He went on to further implore his citizens to take up arms in defense of their country if the Soviets were to ever intend to do to them what they were about to do to Czechoslovakia. The reaction from the Romanians was overwhelmingly positive. This declaration also solidified Romania's developing distance from the Soviet influence and authority, and showed Moscow and the world that Ceaușescu could not be pressured into compliance. He wasn't the only one either. In the West, Canada, Denmark, France, Paraguay and the UK and US were all concerned by this sudden incursion and requested a session The Soviet Union attempted to justify the invasion to their skeptics, saying that it was fraternal assistance for a fellow socialist state. This argument was not convincing enough, and the US ambassador to the UN even went as far in his condemnation to state that that the Soviet Union is, according to Czechoslovakia, is the exact same kind that Cain gave to Abel. Despite all of these criticisms and oppositions, the Soviets and their allies still invaded Czechoslovakia. Roughly 200,000 troops in total crossed the border on the night of August 20th. The local military didn't respond to this attack. Protesters continued to fight back and demonstrate, while journalists and radio stations refused to easily be silenced by the Soviets, but they too were overpowered. Many of Czechoslovakia's leaders were arrested and taken back to Moscow as the Warsaw State stomped out any rebellion they left behind. Even with all the foreign governments denouncing the invasion, no military action was taken to stop it from happening. A week after the invasion began, Dubček was returned to Czechoslovakia from Moscow where he gave a heart-wrenching speech announcing that he had decided, with the Soviets, to put an end to the liberal reforms he had worked so hard for. This slowly destroyed the Dubček administration, and by the summer of 1969, he was ousted from his position in favor of another who helped serve the Soviets' agenda. This aggressive intervention was overall a risky endeavor for the East. Albania was lost from the Warsaw Pact, and Romania put a heavy wedge between its own republic and the rest of the Union and surrounding allies. For the next two decades, Romania stood as an increasingly independent nation from Moscow's authority, and the reason was made abundantly clear during Ceaușescu's bold Bucharest speech. He was convinced that the actions of the Soviets and the other Warsaw states were deeply flawed. For one, because he truly believed that it was not within the ethics of any socialist state to interfere in such a way with another. He also strictly denied the dominance of the Soviets over the rest of the bloc, saying plainly that no one can be an advisor or guide to another socialist state. The decisions must be made and processes carried out by the individual state, party, and people. The Romanian leader was in favor of independence within the bloc, both for his own nation and for his allies. This, coupled with the fact that Romania had already been attempting to sever some of its ties with Moscow, was enough to make Ceaușescu refuse to participate in, and subsequently condemn, the invasion of Czechoslovakia. Some critics from his own party even commented that the speech was an outright mistake and only invited a Soviet invasion, putting all of Romania at risk in what was seen as a useless address. Not entirely useless, though. The speech and Romania's position did bring in support and sudden friendliness from the West. The following year, US President Richard Nixon even paid a visit to Bucharest for a meeting with the Romanian president, who was now seen as the only potential friend within the communist bloc. Whether Ceaușescu knew this reaction would come from the Western world or not may have had an additional influence on his decision to join or condemn the invasion, but either way, it does appear that he would likely have opted out of it at the very least. His strong stance on individualism within the Eastern bloc and his disagreement with the fundamental ethics and strategy behind the invasion could alone be a convincing argument to reject a call to join the other Warsaw Pact states for an intervention.