 France had an alliance with Belgium and with the states of the "Cordon sanitaire", as the French alliance system in Eastern Europe was known.Although the alliances with Belgium, Poland, Czechoslovakia, Romania and Yugoslavia were appreciated in Paris, it was widely understood that this was no compensation for the absence of Britain and the United States.The French military was especially insistent that the population disparity made an offensive war of manoeuvre and swift advances suicidal as there would always be far more German divisions; a defensive strategy was needed to counter Germany.