Because "lines of force" is not the description of electromagnetism that receives the most empirical support with the least superfluous assumptions. Classically, it only awkwardly covers magnetostatics and is inferior to Maxwell's equations, modern formulations of Maxwell's equations in relativistic tensors, and quantum electrodynamics which for the first time relates the mass, charge, and magnetic moment of the electron with high precision and accuracy.
Also, resurrecting a thread so long after your last entry doesn't seem like a good use of your time.
Entered from an iPhone.