What arguments are there in favor of national food self-sufficiency?
Have there been any economists who have argued in favor of national
  food self-sufficiency and what are some of their arguments?


I am not knowledgeable of literature in that direction, but some of the arguments in the aforementioned excerpts are flawed.

Simply put, self-sufficiency does not preclude free trade. The excerpt of The Economist certainly admits that "The notion that free trade precludes food security is plainly wrong-headed", but it still misses subtle differences between security and self-sufficiency: (1) the latter intrinsically entails more autonomy; and (2) the cost of reliance on international markets might ultimately outweigh the costs of pursuing self-sufficiency.

The undeveloped mention of "starving North Korea" in The Economist improperly conflates the notion of food self-sufficiency and North Korea's policy of generalized isolationism. But, more generally, a country may prioritize food self-sufficiency without necessarily imposing trade barriers.

Note that The Economist article mentions Vietnam and India as examples of economies with export restrictions. But an export restriction is consistent with the purposes of self-sufficiency: It aims at ensuring that the domestic production of the commodity is not depleted by international markets prematurely (that is, prior to satisfying the domestic demand). An increased volatility in international markets as a result of the export restriction becomes irrelevant to the domestic economy if the net effect is that its population is not deprived of the commodity it produces.

Likewise, the issue of "domestic farmers [being] discouraged from producing more" has to do with policy (sub-)optimality regarding the excedents from self-sufficiency. It is not a defect inherent to self-sufficiency.

Mohanty's position fares better in that he rather discourages "pursuing self-sufficiency at any cost". But his argument of climate change predictions is self-defeating because a concentration of supply exacerbates a bottleneck risk --and therewith its potential severity-- of a commodity trade. The global impact of extreme weather conditions is predictably worse in the context of fewer exporters than if sources of supply are geographically more diversified because more economies pursue self-sufficiency.