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Contested river crossings have been considered some of the toughest operations in the military. Simply gaining control of the waterway to permit a safe crossing can often be a challenge. Once across the river, a small force will immediately isolated, surrounded by hostiles on three sides with their backs to the river.

Historically, major contested landing operations required one of two things:

• Massive superiority of forces (quantitative and/or qualitative)
• Air superiority

The former presumably requires little explanation. The latter can be a major equalizer by limiting the ability of the enemy to bring reinforcements or supplies against the landing site—helping the equalize the logistical challenges faced by the landing force.

A big part of the challenge for Ukraine is the fact that it doesn’t have either of the ingredients of a successful amphibious landing operation.