  Collisionless plasmas, such as those encountered in tokamaks, exhibit a rich
variety of instabilities. The physical origin, triggering mechanisms and
fundamental understanding of many plasma instabilities, however, are still open
problems. We investigate the stability properties of a collisionless Vlasov
plasma in a stationary homogeneous magnetic field. We narrow the scope of our
investigation to the case of Maxwellian plasma. For the first time using a
fully kinetic approach we show the emergence of the local instability, a
transient growth, followed by classical Landau damping in a stable magnetized
plasma. We show that the linearized Vlasov operator is non-normal leading to
the algebraic growth of the perturbations using non-modal stability theory. The
typical time scales of the obtained instabilities are of the order of several
plasma periods. The first-order distribution function and the corresponding
electric field are calculated and the dependence on the magnetic field and
perturbation parameters is studied. Our results offer a new scenario of the
emergence and development of plasma instabilities on the kinetic scale.
