During the presidential campaign, Donald Trump delighted in waving to packed crowds while the Rolling Stones’ “You can’t always get what you want” played. At the time, the song seemed like a repudiation of the Republican elites who had failed to support his campaign. Today, as his Middle East policy careens off the rails, it’s a concept the President himself should learn to grasp.

Mere hours after Secretary of State Rex Tillerson announced that tensions between Qatar, Saudi Arabia and other regional states were negatively impacting the fight against ISIS and calling for all sides to defuse tensions, the President contradicted him, publicly castigating Qatar for terrorist financing, and backing the Saudis in their campaign against Doha. In this, as in other things, Trump appears not to understand the trade-offs inherent in his own Middle East policies.

Certainly, the rift between Qatar and other Gulf states predates Donald Trump. Tensions have been high for years, particularly during the Arab Spring, when the Gulf states often backed different sides in the political struggles and wars that convulsed the region. As I described in a Cato Policy Analysis in 2014:

“As early as June 2012, media sources reported that Saudi Arabia, Qatar, and Turkey were arming anti-regime rebels [in Syria] with both light and heavy weapons… The vast quantities of money and arms they have provided during the past three years have driven competition among Syria’s rebel groups. This competition has increased the conflict’s duration and has reduced the likelihood that the rebels will eventually triumph.”

This competition was mirrored in other regional states. In Egypt, Qatari money and friendly coverage from their Al Jazeera network helped to propel Mohammed Morsi to power, with Saudi money later propping up the Sisi regime which replaced him. In Libya, Qatar and the United Arab Emirates backed distinct rebel factions, undermining hopes of a settlement and tipping the country back into civil war.

Nor is the President wrong in his assertion that Qatar has a longstanding problem with terrorist financing. The state itself openly supports Hamas, and has long been one of the more ‘permissive’ jurisdictions for private citizens to finance extremist groups throughout the region. As David Cohen, former Undersecretary for Terrorism and Financial Intelligence at the Treasury Department noted in 2014:

“Qatar has become such a permissive terrorist financing environment, that several major Qatar-based fundraisers act as local representatives for larger terrorist fundraising networks…”

But today’s anti-Qatar coalition is less concerned about this. Indeed, Saudi Arabia and the United Arab Emirates have themselves backed extremist groups in regional conflicts; Kuwait is a key center of regional terrorist financing. Instead, these states are concerned primarily with Qatar’s relatively independent foreign policy, and its willingness to back political groups like the Muslim Brotherhood which can pose a domestic political threat to them.

The crisis has resulted in closed borders and airspace, and created the potential for food and supply shortages in Qatar. For the United States, these restrictions have a real and negative impact on America’s anti-ISIS campaign, which is largely based out of Qatar’s Al Udeid airbase. The approximately 10,000 U.S. troops based in Qatar are also a major concern, though one the President has yet to mention.

Indeed, despite these concerns – and despite the efforts of Tillerson, Mattis and others to mediate the dispute, and to walk back the President’s rash tweets – Trump himself appears determined to publicly take the Saudi side in this dispute and force unity within the GCC. In doing so, he risks raising regional tensions, and complicating the anti-ISIS campaign that was the cornerstone of his campaign.

Foreign policy often requires trade-offs. It is no doubt possible that long-term pressure from regional states may induce Qatar to scale back the scope of its foreign policy. But this will come at the cost of other U.S. foreign policy objectives in the region. As the President will eventually learn, in foreign policy, you really can’t always get everything you want.