Nobody here has made much mention of Cassius, he of the lean and hungry look, and dangerous. Also, the main reason was that “Caesar was ambitious.” The usual take is that he wanted total power in Rome. Then I read a two century old history book which gave me a very different perspective.
Early in Caesar’s career, he was part of the triumvirate, Pompey in the West (Spain/North Africa, Crassus in the East (Syria, Palestine, etc., and Caesar in the center (Rome and Europe). General Crassus was in his 50’s and eager to make a big name for himself before he got too old to lead troops. He decided to go after the Parthians (a BIG mistake, Google more). Cassius was a young officer with his troops. Crassus f***ed up in a number of ways, got himself and his son killed, and Cassius managed to round up about 10,000 troops and retreat to Syria which prevented the Parthians from taking that importance Roman province.
Fast forward 20 years to our assassination story. Caesar, who was now sole ruler of Rome (defeated Pompey, and Crassus dead), decided to enhance his glory by defeating the Parthians and restoring Rome’s honor and avenging that loss and death of Crassus et al. Having been there himself, Cassius knew this was a terrible idea, and very bad for Rome in general. Thus the plot to kill Caesar for too much ambition. Having now spent/wasted? much of our treasure in Afghanistan and Iraq, I think perhaps he was a wise and prescient plotter.
You are right, as an aside Crassus was in effect a very wealthy real estate developer and military success was a way to higher office. He simply was in over his head in military matters.
Here’s a work about Crassus from nineteen centuries ago:
http://classics.mit.edu/Plutarch/crassus.html
The Parthians had a good army and effective tactics against the Romans’, and had a massive numerical advantage, plus better intel. This is not to sell Crassus short, he made some wrong decisions, but as the saying goes, hindsight is 20/20. Instead of working with a local ally, he allowed the Parthians to chop up both piecemeal. Marc Antony was a drunken ass-wrangler who tended to take his eye off the ball a bit much. When he made his half-assed attempt to avenge the death of Crassus, he was also at a disadvantage when a good bit of what Roman population lived in the east turned against him and against Rome. Over a century later, Trajan spent a couple of years smashing the crap out of the Parthians, taking their capital, annexing Mesopotamia, and probably literally washing his sword in the waters of the Persian Gulf. He died there, and his supposedly adopted son, Hadrian, gave up those conquests, and spent most of his reign banging young boys and traveling through the Empire, apparently avoiding Rome.
http://ancienthistory.about.com/cs/people/a/crassus.htm
http://www.historynet.com/mark-antonys-persian-campaign.htm