Explain the quote "The Weapons with which the bourgeoisie felled feudalism to the ground are now turned against the Bourgeoisie itself"?

This particular concept that Marx and Engels explore helps to illuminate what they see as the imminent critique within capitalism.  The argument here is that the "weapons" used by the bourgeoisie was the desire for material wealth and the coveting of profit.   The belief argued was that through this profit hoarding desire and the institutional apparatus of power that supports it, the progression of material stages of history (dialectical materialism) eliminated feudalism and ushered in the stage of capitalism.  At the same time, Marx and Engels argue that this is not the final stage of growth and development.  Rather, that capitalism will inevitably give way to an order where the Proletariat will assume control and deconstruct the capitalist power structures.  In the historical and economic inevitability which allowed the usurpation of feudal control to a capitalist order, the same fate will befall capitalism and the emergent bourgeoisie.