May 16, 2019

U.S.-Iran Tensions Escalate
Overview
U.S.-Iran tensions have escalated in recent weeks as the
Trump Administration has taken several significant steps in
its campaign of applying “maximum pressure” on Iran, and
Iranian leaders have announced responses. U.S. steps have
included designating Iran’s Islamic Revolutionary Guard
Corps (IRGC) as a Foreign Terrorist Organization (FTO),
reimposing sanctions on any country that buys Iranian oil,
ending sanctions waivers for some assistance to the
permitted aspects of Iran’s nuclear program, and imposing
new sanctions on transactions in some Iranian commodities.
U.S. officials state that reports about potential Iran-linked
threats to U.S. forces and interests prompted the
Administration to send additional military assets to the
region. Yet, press reports on May 16 indicate that President
Donald Trump prefers a diplomatic solution to continued
escalation that could lead to conflict.
Members of Congress have been requesting additional
information from the Administration about the uptick in
U.S.-Iran tensions. Congress might consider the broader
Administration’s Iran policy or the potential for use of force
against Iran.
Recent Administration Steps to Pressure Iran
Recent Administration efforts to increase pressure on Iran’s
economy and government include:

determined by the Administration to have conducted
significant transactions with Iran’s iron, steel,
aluminum, or copper sectors. These commodities
account for about 10% of Iran’s exports, but the exports
primarily go to regional companies that might not be
easily penalized by U.S. sanctions.
[The U.S. military deployments] send a clear
and unmistakable message to the Iranian
regime that any attack on United States
interests or on those of our allies will be met
with unrelenting force.
Statement by National Security Adviser John Bolton,
May 5.
What they [Iranian leaders] should be doing is
calling me up, sitting down; we can make a
deal, a fair deal. ... We're not looking to hurt
Iran…But they should call, and if they do, we're
open to talk to them.
President Donald Trump, May 9.
We don’t seek a war, and they don’t either.
They know it’s not in their interests.
Iran’s Supreme Leader Grand Ayatollah Ali Khamene’i,
May 14.

 On April 8, 2019, the Administration designated the

IRGC as a Foreign Terrorist Organization (FTO). Iran’s
parliament responded by enacting legislation declaring
U.S. Central Command (CENTCOM) and related forces
in the Middle East to be terrorists.

 As of May 2, 2019, the Administration ended a U.S.
sanctions exception for the purchase of Iranian oil to try
to drive Iran’s oil exports to “zero.”

 On May 3, 2019, the Administration ended waivers
under the Iran Freedom and Counter-Proliferation Act
(IFCA, P.L. 112-239) that allow countries to help
remove Iranian heavy water and low-enriched uranium
that exceed JCPOA stockpile limits.

 On May 5, 2019, citing reports that Iran might be
preparing its allies to attack U.S. personnel or
installations, National Security Adviser John Bolton
announced that the United States was accelerating the
previously planned deployment of the U.S.S. Abraham
Lincoln Carrier Strike Group to the region and sending a
bomber task force to the Persian Gulf region.

 On May 8, the President issued Executive Order 13871,

Iranian Reaction
Iran’s reaction to the U.S. steps appears to reflect an
attempt to avoid outright conflict with the United States
while indicating that Iran will not bow to U.S. pressure.
Some Iranian statements have appeared provocative,
including threats by the IRGC Navy Commander to close
the Strait of Hormuz if Iran could not export any oil, but
Iran historically has issued similar threats that are not
followed by concrete actions. On the other hand, in May
2019, Iranian Foreign Minister Mohammad Javad Zarif’s
offered to negotiate a swap of detainees held by both sides.
On May 8, President Hassan Rouhani announced that Iran
would no longer abide by restrictions of the 2015
multilateral nuclear agreement (Joint Comprehensive Plan
of Action, JCPOA) on stockpiles of low-enriched uranium
and heavy water. He also announced that unless the
European Union (EU) countries that have sought to
preserve the JCPOA “fulfill their commitments” to provide
economic benefits of the JCPOA within 60 days, Iran
would resume additional aspects of uranium enrichment,
including possibly enriching to a higher level of purity.

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 U.S.-Iran Tensions Escalate

European Responses
The EU has sought to de-escalate tensions and urged Iran
not to leave the accord entirely. A May 9 joint statement by
the EU and the foreign ministers of France, the United
Kingdom, and Germany stated that “We reject any
ultimatums” by Iran but, “At the same time we recall our
own firm commitments under the agreement including as
regards sanctions lifting…” Secretary of State Pompeo
attended meetings with EU officials on May 13, reportedly
to brief the EU on U.S. information about alleged Iranian
planning for attacks on U.S. interests in the region, but
press reports indicate that EU officials are skeptical that
actions by Iran represent a materially new threat. UK
Foreign Secretary Jeremy Hunt stated, “We [EU] are very
worried about the risk of a conflict happening by accident,
with an escalation unintended really on either side.”
Scenarios and Possible Outcomes
There are several directions the escalating tensions might
take, any of which might involve congressional oversight,
potential considerations of new sanctions, authorization or
limitations on the use of military force, or congressional
steps to support regional partners that could be affected by
possible conflict. Iran’s Islamic Revolutionary Guard Corps
–Qods Force (IRGC-QF) arms, trains, and advises allies
and proxies throughout the Middle East region, including in
Syria, Lebanon, Iraq, Yemen, and Bahrain. Accordingly,
Iran and/or its allies have numerous ways to take aggressive
action or counter U.S. actions. The published State
Department report on international terrorism has
consistently asserted that Iran and its key ally, Lebanese
Hezbollah, have a vast network of agents in Europe, Latin
America, and elsewhere that could act against U.S.
personnel and interests far outside the Middle East.
On May 15, the State Department ordered “nonemergency
U.S. government employees” to leave U.S. diplomatic
facilities in Iraq. This led to speculation that the
Administration sees a heightened threat of Iranian allies
acting against the United States there. In addition, U.S.
Central Command issued a statement that recent comments
of the Baghdad-based British deputy commander of
Operation Inherent Resolve (OIR) “run counter to the
identified credible threats” from Iran or allied militias in
Iraq or Syria.
Escalation. U.S. and Iranian officials have said they do not
want armed conflict. However, the tensions have the
potential to evolve to that point, perhaps by miscalculation.
Assertions on May 12-13 by the United Arab Emirates and
Saudi Arabia that several of their oil tankers had been
“sabotaged” or “vandalized” and reports of attacks on Saudi
oil pipeline infrastructure signal the potential for any
incident to raise the risk of a clash that may or may not
escalate into wider conflict. Iran denied involvement in the
incidents, but findings of responsibility for the tanker
incidents have not been publicized.
A New York Times report on May 14 indicated that the
Administration might significantly increase the U.S. force
posture in the region if Iran attacks U.S. interests or takes
steps toward developing a nuclear weapon. There are over
60,000 U.S. forces stationed in various military facilities in

the region, particularly in the Arab states of the Gulf
Cooperation Council (GCC: Saudi Arabia, Kuwait, UAE,
Qatar, Oman, and Bahrain). Press reports indicated that the
number of forces might expand to up to 120,000 if the
reported option is exercised. On May 14, President Trump
dismissed the report, saying “We have not planned for
that.” But he added that “If we did that, we’d send a hell of
a lot more troops than that.” Whether the Administration
adds forces to the region, the United States has the
capability to implement a range of options such as air
strikes on Iranian targets.
Status Quo. The tensions could remain, but neither escalate
nor de-escalate, particularly if the U.S.-Iran discourse
remains mostly bellicose but without any significant violent
incidents that are attributed to either the United States or
Iran.
De-Escalation. Iran could potentially try to de-escalate,
perhaps by taking up U.S. offers to negotiate a broader,
revised JCPOA, though U.S. demands for a new JCPOA are
extensive and many see that as unlikely. De-escalation
could also involve mediation by regional states such as
Oman or Qatar, which have ties to both Iran and the United
States. Qatar’s Foreign Minister visited Iran on May 15
reportedly to discuss de-escalation of the U.S.-Iran tensions.
A May 16 Washington Post report indicated that President
Trump wants to de-escalate tensions, avoid conflict with
Iran, and negotiate a revised JCPOA.
Potential Implications for Congress of Escalation
The reports of Administration plans for possible military
action against Iran reportedly prompted some in Congress
to request that the Administration brief Congress on its Iran
plans and policies, and Members might explore a number of
questions in engaging executive branch officials.
One question is that of authorization for the use of military
force against Iran. No legislation has been enacted
authorizing the use of force against Iran, although
successive Presidents have asserted legal and constitutional
authority to initiate any military operation. At a Senate
Foreign Relations Committee hearing on April 10, 2019,
Secretary of State Pompeo, when asked if the
Administration considers the use of force against Iran as
authorized, answered that he would defer to Administration
legal experts on that question. However, he suggested that
the 2001 authorization for force against those responsible
for the September 11 terrorist attacks could potentially
apply to Iran, asserting that “[Iran has] hosted Al Qaida.
They have permitted Al Qaida to transit their country.
There-there’s no doubt there is a connection between the
Islamic Republic of Iran and Al Qaida. Period. Full stop.”
A relevant, pending item of legislation in the 116th
Congress, the Prevention of Unconstitutional War with Iran
Act of 2019 (H.R. 2354/S. 1039) would prevent the use of
funds for “kinetic military operations in or against Iran”
except to repel or prevent an imminent threat to the United
States.
Kenneth Katzman, Specialist in Middle Eastern Affairs

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 U.S.-Iran Tensions Escalate

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