'Operation Cobra' —as stated by Red— was the phase of a campaign and 'Operation Bagration' was a whole campaign on itself. There's actually no comparisson at all between the two.

'Bagration' lasted two months, it advanced 600 km, it —along simultaneous operations in its flanks— kicked the enemy out of their territory, destroyed Army Group 'Centre', surrounded Army Group 'North' and isolated Army Group 'South' and of course, killed, fatally wounded or captured more than 500.000 enemy troops and reached the river Vistula, leaving almost no German soldiers between Warsaw and Berlin. It broke the backbone of the German Armed Forces in the east.

Of course the fact that it happened at exactly the same time than the Normandy campaign —which destroyed the German forces in the west along some 250.000 men— made 'Bagration' easier and to cause greater impact.

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"War is less costly than servitude, the choice is always between Verdun and Dachau." - Jean Dutourd, French veteran of both world wars

"A mon fils: depuis que tes yeux sont fermes les miens n’ont cessé de pleurir." - Mère française, Verdun