Many countries are still separating some plutonium, however, in case uranium one day grows scarce and costly.

Your article says that malaria "hinders economic development"; epidemics are growing ever more costly in terms of health, development, trade and tourism.

Protection bets grow more costly with each voyage.

At first I didn't even notice that mistakes were starting to pile up and grow costly.

But the luxury of such ambivalence is growing more costly.

As health coverage has grown more costly, many people have been skimping on care, and millions of Americans are going without health insurance altogether.

The war is growing increasingly costly for Yugoslavia.

And the proposed space station grew so large and costly that it had to be scaled back somewhat.

Then knightly armour grew more elaborate and costly throughout the century.

Over the years, as the Guild building grew more costly to maintain, the influence of unions also waned, reducing rental income when operations closed down.