As the current U.S.-Turkey row shows all too clearly, mixing and matching the latest Russian and U.S. weapons systems is something Washington does not take lightly.

If China genuinely wishes to dominate its region it will need to make rather fewer missteps.

Whether the United States and its allies would go to the same length to support an ally today remains a very open question.

Cross-border investment and globalization is no longer seen as one of the major guarantors of international peace.

While the figure at the top might change, the military-dominated power structures beneath may prove much harder to shift from power.

Beijing is becoming much more assertive right up to territory held by other nations, both with military force and "civilian" vessels.

If the race for ever more powerful weapons now extends beyond the sky, there is no telling where it might end.

The loss of the U.S.'s long-running military technical edge is clearly a major concern within the Pentagon.

The outside world should not cave in to Beijing's pressure to turn a blind eye.

Artificial intelligence is creating new avenues for war in what could be the century's defining arms race.