When Leon arrived in Moscow, it was 09:00 PM. From above, he could see that the city had recovered a lot more than New York. Based on the number of houses, he concluded that Moscow had at least three hundred thousand survivors. That was three times more than New York.
Confirming what Seiji said, there was a wall made of steel being constructed around the city. Leon thought of doing similar in Las Vegas, but it would take a few months before he could do so. The size, weight, and durability of those steel plates have to be decent. Otherwise, there was no point in using them to create a wall. Anyway, the survivors of Las Vegas would have to meditate for four hours every day for three months before any of them have enough mana and intelligence to make a steel plate.