DW: In its report on military expenditure around the world in 2017, the Stockholm International Peace Research Institute (SIPRI) established that there had been a slight increase in spending. The report says that, around the world, $1.73 trillion (€1.45 trillion) was invested for military purposes. That's 1.1 percent more than in 2016. Is this a lot or a little?

Pieter Wezeman: If we take into account statistical imprecisions and the fact that the data is never absolutely reliable, we can say this is a minimal rise. It's also clear that on a global scale, military spending has stabilized at a high level. At a regional level, we see quite considerable differences.

In China, for example, expenditure rose by 5.6 percent, to a total of $228 billion.

Yes — but it's in line with the rise in expenditure over the past 20 years. Military spending there keeps pace with the rise in gross national product. So it's not a particularly dramatic development. However, China is the world's second-highest investor in military spending. It's well behind the biggest investor, the United States — but also well ahead of the next countries on the list.

What does this tell us about the country's political ambitions?

China is a very big country with a very large economy. China doesn't want to be just a regional power; it wants to be a global one. China has big ambitions, and they're reflected in its military spending.

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You mentioned the United States, which has also increased its spending. It's investing more in its military than the total spending of the next seven countries in the ranking. What does this mean?

US President Donald Trump has already pushed through a bigger budget — although he's facing considerable opposition, because there are many influential voices in the States calling for a reduction in spending. But for the time being, Trump has prevailed. We can expect to see higher expenditure in the coming years as well.

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Military spending is particularly high in the Middle East. Seven of the 10 countries whose arms spending is highest in relation to gross national product are located in the region. These include Oman, Saudi Arabia and Kuwait, as well as Jordan, Israel and Lebanon. What's your view of the military developments in this region?

Saudi Arabia, the United Arab Emirates and Qatar are prepared to invest very large amounts of their gross national product in their military budgets. With Saudi Arabia, for example, it's more than 10 percent. This is a very clear expression of how these countries view their position in the region.

With Saudi Arabia, that number also expresses the extent to which the country is watching its main rival, Iran. The wars in Syria and Yemen also show that these countries are not only increasing their spending, they're also prepared to use these weapons to achieve their aims.

Iran, on the other hand, invests relatively small amounts in its military. That may well change, though. Iran is certainly willing to increase its spending, but its economic situation won't permit this at the moment.

The African continent registered a minimal downturn of half a percent. How do you explain this downturn?

There are various different reasons. Angola, for example, has reduced its spending. That's because of the drop in the price of oil, which of course also affects Angola. The same is also true of several other African countries that depend on oil revenue.

In some countries, though, expenditure has increased — in Sudan, for example. The fighting between government troops and the rebels has intensified. That also has a marked effect on the military expenditure of Angola and other countries. Overall, though, the situation differs greatly from one country to another.

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Military spending has risen by 12 percent in Central Europe, and in Western Europe by 1.7 percent. Is this connected to a sense that they are threatened by Russia?

The European countries are reacting to developments they perceive as threatening, above all the situation in Ukraine. Russia has, in fact, increased its military spending considerably over the past 10 years. As a result, the European countries in turn see themselves forced to increase their spending — Poland, for example. NATO has also increased its troop strength in the region.

It must, however, be noted that Russia's spending has not increased this time; in comparison with 2016/17 it has even gone down. These numbers should now be taken into greater account when people in Europe talk about spending more on defense. We could even ask ourselves whether this isn't the right time for us to limit our military spending as well — and in doing so, to demonstrate that we're willing to resolve the conflict in a different way.

Pieter Wezeman is a senior researcher with the Arms Transfers and Military Expenditure Program at the Stockholm International Peace Research Institute (SIPRI).

The interview was conducted by Kersten Knipp.