What major US military conflicts occurred from 2017 to 2021 under Donald Trump?

Checked on December 9, 2025
Disclaimer: Factually can make mistakes. Please verify important information or breaking news. Learn more.

Executive summary

From 2017–2021 the Trump administration did not open a new large-scale, prolonged interstate war, but it did order multiple major military actions and oversaw continued U.S. engagement in ongoing conflicts: notable events include two U.S. cruise‑missile strikes on Syrian government targets (2017 and 2018), the January 2020 strike that killed Iranian general Qasem Soleimani and the subsequent Iranian missile strikes on U.S. forces in Iraq, and a drawdown and negotiated exit process in Afghanistan culminating in the 2020 U.S.–Taliban deal and the later troop withdrawal planning [1] [2] [3]. Sources disagree on whether those steps amount to “new wars” versus continuations or escalations of existing conflicts [4] [5].

1. Trump ordered strikes in Syria to punish chemical attacks

In April 2017 Trump authorized a 59‑Tomahawk cruise missile strike on a Syrian airbase in retaliation for a suspected chemical attack by the Assad regime, and he ordered additional strikes in 2018; mainstream reporting and administration statements treat those as significant kinetic actions though not the start of a new protracted war [1] [6] [5].

2. The killing of Qasem Soleimani and the escalation with Iran

In January 2020 the administration ordered the strike that killed Iranian Quds Force commander Qasem Soleimani, a discrete but major use of force that produced Iranian retaliatory missile strikes on U.S. forces in Iraq and raised questions about risk of a wider conflict; reporting highlights both the operational impact and political controversy around that choice [2].

3. Afghanistan: negotiations, drawdown and the 2020 deal with the Taliban

Trump pursued a policy of drawing down U.S. troops in Afghanistan, and his administration negotiated the February 2020 agreement with the Taliban that set conditions for a U.S. withdrawal; the deal and subsequent reductions were a central foreign‑policy achievement and a key change in a long‑running conflict rather than a new war [3].

4. Iraq and Syria: continued intervention without new large deployments

The Trump presidency continued U.S. military involvement in Iraq and Syria inherited from prior administrations — sustaining counter‑ISIS operations, carrying out targeted strikes (including the Syrian strikes cited above), and reducing but not fully ending troop presences — a mix of escalation in certain moments and drawdown in others [5] [6].

5. Debate over whether Trump started any “new” wars

Fact‑checkers and analysts note that Trump “did not enter U.S. troops into a new conflict” in the sense of starting a sustained, congressional‑authorized war, while many commentators argue he nonetheless used force repeatedly and escalated specific theaters [4] [7]. Conservative and establishment analyses (AEI, Hoover) stress continuation of prior interventions with targeted strikes under Trump, not new protracted wars [5] [8].

6. Critics say “no new wars” understates real violence and escalation

Several outlets and analysts argue the “no new wars” framing misses important realities: Trump expanded or intensified certain operations (bombing campaigns, support for partners such as in Yemen), increased incidents that risked wider escalation (e.g., Iran episode), and presided over tense crises with North Korea and elsewhere that risked major conflict [9] [10] [2].

7. How to read the disagreement: legal labels vs. operational reality

Much of the dispute is definitional: sources that emphasize formal measures note no declaration of war or new congressional AUMF; others focus on operational facts — missile strikes, targeted killings, troop reductions or transfers, and proxy support — and treat those as meaningful uses of force with long-term consequences [4] [5] [6].

8. What reporters and historians flag as the lasting impacts

Analysts point to durable policy outcomes from 2017–2021: a negotiated path to U.S. withdrawal from Afghanistan, constrained but persistent counter‑ISIS and Middle East operations, heightened U.S.–Iran confrontation after Soleimani’s killing, and an administration that used targeted strikes as a regular tool of policy — outcomes that shaped subsequent crises even if they did not create a new declared war [3] [2] [5].

Limitations: available sources do not provide a comprehensive chronology of every U.S. military action from 2017–2021 in this dataset; the claims above are drawn from the supplied reporting and analyses and reflect areas where those sources agree or disagree [1] [3] [5] [4] [2].

Want to dive deeper?
What were the key US military operations in Afghanistan between 2017 and 2021?
How did US involvement in Syria change during the Trump administration?
What airstrike campaigns did the US conduct against ISIS from 2017 to 2021?
What were the major US-Iran military confrontations and incidents in 2019–2020?
How did US troop levels and deployments shift in Iraq under President Trump?