"s."According to the researcher Jan Sowa, the Commonwealth failed as a state because it was not able to conform to the emerging new European order established at the Peace of Westphalia of 1648. Poland's elective kings, restricted by the self-serving and short-sighted nobility, could not impose a strong and efficient central government with its characteristic post-Westphalian internal and external sovereignty. The inability of Polish kings to levy and collect taxes (and therefore sustain a standing army) and conduct independent foreign policy were among the chief obstacles to Poland competing effectively on the changed European scene, where absolutist power was a prerequisite for survival and became the foundation for the abolition of serfdom and gradual formation of parliamentarism.