The elements are different. Typically “conspiracy to commit X” requires some number of people agreeing to do X and then someone from the group doing at least one overt act in furtherance of that agreement. So you can be guilty of “conspiracy to commit X” without ever getting even remotely close to doing X.
So for example if two mates talk about that they are going to kill person Y, that is the agreement. And then one of them buys a gun, that is an overt act. And even if person Y has very good security, and the two dudes have no chance in hell of murdering Y ever, that is still a “conspiracy to muder” charge.
> So you can be guilty of “conspiracy to commit X” without ever getting even remotely close to doing X.
Probably most legal systems have something like that.
The interesting thing about US law - at least compared to German law (a Civil law country) - is the fact that even if you succeed with X, you can still be charged with conspiracy to commit X on top.
If I remember correctly, it has its roots in the RICO statutes which arose from FBI attempts to break up the mafia. The idea was to make it easier to prosecute people who did not actually pull the trigger but who were involved in planning and ordering of such crimes.
Now, a wiretap of a boss ordering a hit could result in the same sentence as the gunman.
Unfortunately it has been abused greatly, including drivers who never got out of the car sentenced to death for a 7/11 robbery gone bad, etc.
Further, as you can imagine, it gives the prosecution massive (many would say unfair) leverage over associates to a crime, given that they could face the same, full sentence if they don't cooperate. It's a major reason behind the enormous percentage of criminal charges not going to trial.
So for example if two mates talk about that they are going to kill person Y, that is the agreement. And then one of them buys a gun, that is an overt act. And even if person Y has very good security, and the two dudes have no chance in hell of murdering Y ever, that is still a “conspiracy to muder” charge.