The presidency of Donald Trump is merely accentuating the gradual loss of interest by the United States in the European Union and Europe that had already begun with the end of the Cold War and accelerated with the 9/11 terrorist attacks and subsequent American-led wars in Afghanistan and Iraq.
Although the European Union remains the largest trading partner of the United States with an annual trade volume of $699 billion and with almost 80,000 U.S. military personnel still stationed in Europe, the focus of Washington, after a decade-long interlude in the Middle East, has shifted to the Asia-Pacific region. This is not likely to change under a President Trump.
The 45th President of the United States will likely pay little attention to the European Union and Europe as he struggles to fulfill his campaign promises of swiftly defeating ISIS, implementing domestic health care reforms, and enforcing new nationalist and protectionist trade policies. Given Trump's inattention, compounded by an overall decline in U.S. relative power and the gradual establishment of a more multipolar world order, Europe will increasingly have to fend for itself over the next four years.
While cooperation in the field of counterterrorism and intelligence will likely remain robust, Donald Trump's new policies will have a number of consequences in the security realm for Europe over the next four years.
First, Europe and the European Union will increase defense spending and look for defense arrangements outside the U.S.-dominated North Atlantic Treaty Organization (NATO) over the next four years. One sign for this is the launch of a so-called Permanent Structured Cooperation on defense spending and projects among a number of EU member states slated for March 2017. With the United Kingdom leaving the European Union, bilateral defense arrangements in Europe may also gain more prominence in the years ahead. Europeans will also begin a serious discussion on the establishment of a European nuclear umbrella--a particularly politically sensitive subject for Europe's most powerful country: Germany.
Second, European countries, while increasing defense spending, will also seek a new less confrontational modus operandi with Russia, the principle state-based military threat to Europe. Consequently, it is unlikely that economic sanctions imposed following the unilateral Russian annexation of Crimea in 2014 will continue given President Trump's likely rapprochement with Vladimir Putin. As a result, pressure inside the EU, presumably spearheaded by Germany, will increase to lift the sanctions. (Particularly, since, according to some studies, sanctions negatively impacted employment across the EU.) A new relationship with Russia will entail tacitly accepting that Eastern Ukraine falls under Russia's sphere of influence and that Kiev's aspiration to join the EU will not succeed in the near term.
Third, with the United States no longer the guarantor of the international world order, Europe paradoxically will seek deeper ties with the People's Republic of China to uphold the current system. This, to name a few, will include defending the World Trade Organization and the global free trading system; the Iran deal, which Trump will likely abandon; the Paris Agreement on Climate Change which a Trump White House might also abandon; and the deeper integration of Europe--China was decidedly in favor of the United Kingdom remaining in the EU prior to the Brexit vote and has been a consistent supporter of the European integration process to facilitate Chinese investment in Europe. As a result of stronger Europe-China ties, human rights issues will likely be less discussed in international forums during the next four years.