Two weeks ago, that was the reason for slapping tariffs on US steel and aluminium imports.
This lifted eyebrows given flagging inhabitant confidence concerns allows the US to equivocate punishment under World Trade Organisation (WTO) manners for what many courtesy as a protectionist measure.
It has been seen as exploiting a loophole that risks undermining the WTO if other countries respond similarly.
Then overnight, Mr Trump cited inhabitant confidence in selecting to block Singapore-based chipmaker Broadcom’s $117bn takeover bid for US rival Qualcomm, even nonetheless a understanding had nonetheless to be reached.
The White House argued that Broadcom’s plans for Qualcomm would lead to investment cuts, harming America’s ability to contest in 5G record with Chinese rivals.
In other words, he was effectively accusing the Singaporean company of behaving as a front for the Chinese.
To some, Mr Trump’s movement will seem complicated handed, given it was rarely doubtful in any case that the takeover would have got past foe regulators in the EU and China.
It was also doubtful to pass pattern in Washington given the Committee on Foreign Investment in the United States (CFIUS), a row shaped from several US supervision agencies that effectively acts as an judge of several takeover deals, had already warned the takeover could act against US inhabitant security.
That involvement was itself rarely poignant given CFIUS, a physique set up by Gerald Ford in 1975 in response to ascent concerns over Japanese tenure of the US wiring industry, tends not to meddle on a understanding before it has even been finalised.
It has been seen by US foe lawyers as an abuse of the committee’s powers.
Rarer still is presidential intervention.
There have only been 4 prior such moves: George HW Bush’s decision to retard the Chinese takeover of an aircraft tools builder in 1990; Barack Obama’s decision to retard the construction of a Chinese-owned breeze plantation nearby a US air bottom in 2012; Mr Obama’s decision to retard the Chinese takeover of a German chip tools builder in 2016 and Mr Trump’s decision last year to retard the Chinese takeover of a US chipmaker.
That decision, last September, also followed a warning from CFIUS that the understanding threatened US inhabitant security.
Broadcom will be immensely undone at Mr Trump’s decision.
Its arch executive, Hock Tan, was welcomed to the White House as recently as November, when he announced plans to redomicile Broadcom in the US.
On that occasion, Mr Trump pronounced Mr Tan, a Malaysian-born US citizen, was “a great, good executive” and described Broadcom as “one of the really great, good companies”.
Ironically, had that redomiciling left ahead, CFIUS would have found it tough to retard the Qualcomm takeover.
Broadcom will not be the only party left disappointed.
This deal, a record for the tech sector, betrothed to be a immeasurable money-spinner for the Wall Street banks that had lined up some-more than $106bn (£76bn) worth of appropriation for it.
The indictment that Broadcom is a front for China, meanwhile, is spurious.
Broadcom was founded in the US by a highbrow and tyro from the University of California, Los Angeles and has only been incorporated in Singapore given its 2016 takeover by Avago Technologies, another all-American company that began life as the chips arm of Hewlett-Packard, which happened to be domiciled in Singapore for taxation reasons by its prior private equity owners.
The bigger picture here is that Mr Trump’s policy of America First means the US is apropos some-more protectionist.
Blocking a understanding before it has even been concluded is flattering strident.
CFIUS has already blocked a series of takeovers of US companies given Mr Trump became boss and the use by the White House of its report last week, in justifying this decision, suggests it will be used again in the future as partial of the President’s policy arsenal.
A asocial interpretation of this decision is that the Trump administration is fortifying a struggling company already under encircle – it faces countless lawsuits from Apple, its largest customer, as good as from abroad – for abusing its mobile patents to kill competition.
The risk is that it dissuades unfamiliar companies from investing in America.
And, for Silicon Valley in particular, there may now be the hazard of larger sanctions from China in response.
Apple, Microsoft and, indeed, Qualcomm itself are among the many US tech companies deriving increasingly vast chunks of their revenues from China.
That may, after Mr Trump’s latest decision, come at a aloft cost to them.