The bridge
This probably won't surprise the reader of this book because the bridge is mentioned in the title, but The Bridge at Andau is a major symbol in this book because of its real historical importance. This natural symbolism is explored through lengthy conversations amongst the characters who are left to scramble and think on their feet as war makes refugees out of them. The bridge is a salient reminder of the natural difficulty of expatriation, movement, and life as a refugee. It is a symbol for fateful change.
Surveillance and paranoia
The people in this book are paranoid because of the government's tendency to surveil the public. This is only intensified by the rebellion. The Soviet forces push into Hungary with their full force, and the people are split in their opinion about how to respond. Although some flee, many try to stay, only to find that warfare has made the government oppression even heavier. Now, the government has secret agents who spy on the public, making a paranoia amongst the people about whom they can trust. The real historical truth of this aspect of Soviet history provides a natural symbolism for paranoia.
Man versus tank
This novel offers a moment in time similar to the famous picture of Tiananmen Square where the man versus man conflict is extremely one-sided. On one side, the rebels fight in vain (it seems) to fend off the threat of full-on Soviet invasion. The other side has tanks and war machines that the Hungarian people simply could not fight on their own. The moment stands as a reminder that the balance of human governments has become precious in light of technological advances.
Budapest and time symbolism
Budapest is a natural symbol for older times because of the extremely rich and dense cultural history of the city. The Soviet invasion effects that history in a radical way because it threatens hundreds and hundreds of years of human history with a new agenda that takes the past as a mistaken era. The Soviet spin on Communism threatens Budapest in a similar way to the historical tragedy of the burning of the Library of Alexandria. Budapest and their autonomy are a symbol for human culture and the value of different ways of life. The book points to the importance of preserving those ways of life.
The historical element
As the reader might notice in the above sections, there is a strikingly relevant nature to this book, even though it happened in the past. This is an indication that human history has an allegorical quality, because the people in this book are inherently similar to the humans who are alive today. That includes the Soviets, in fact, and so the value of studying history is made plain by motif: It is clearly important that people study the events of history so as not to repeat the horrible and socially destructive mistakes of yesteryear.