The US Supreme Court¡¯s decision to uphold President Trump¡¯s travel ban ¨C more honestly a??¨C naturally and rightfully raises to prominence again the question of where responsible scientists should hold their international conferences. We may soon see renewed calls to , in solidarity with the many scientists around the world who can no longer attend conferences held in the US. But whether or not an outright boycott may be warranted, responsible scientists clearly have some choice in where to organise future conferences.

Many scientists are, I think rightly, suggesting that we should move more, if not most, of our international scientific conferences outside the US. There is some . Against this suggestion, however, I have often heard the objection that doing so ¡°¡±. While true on the surface, this is a weak and rapidly fading excuse to abdicate responsibility, for two clear reasons: numbers, and choice.

First, consider the relevant numbers, and more importantly their trend. Of the population of scientists affected by Trump¡¯s Muslim ban, we can ask: are there more scientists outside the US who are now unable to attend US-based conferences, or are there more currently in the US who now cannot readily travel outside? While I do not have the figures at hand to perform a precise comparison, one fact is clear: the number of scientists who can enter the US is decreasing.

Since prominent international conferences take time to organise, those whose locations have not already been determined are likely to be at least a year away. It seems safe to predict that by then, the pipeline of students affected by the travel ban will already be nearly dry. For this reason, the balance of pursuing the ¡°greater good¡± ¨C or least harm ¨C must clearly weigh in favour of the banned scientists outside the US.

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Of course, some affected scientists do have long-term jobs in the US, including faculty positions. However, faculty and other established scientists often have the option of sending students or colleagues to present and participate at international conferences on their behalf ¨C and often do so anyway because of time constraints or other reasons. And those scientists who do have permanent US jobs eventually have the option of applying for US citizenship, which formally , if not from the racism and bigotry behind it.?

Numeric trends aside, there is a second clear reason why we must place the interests of affected scientists outside the US ahead of those currently in the US. The affected scientists in the US may not be able to leave the country to attend conferences without risking their visas, but at least they have a choice of how and when they wish to leave. Affected scientists outside the US have no such choice. Their exclusion is unconditional, permanent and completely outside their control, at least as long as Trump¡¯s travel ban remains in effect.

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Yes, there are other ways to mitigate the damage of Trump¡¯s policies, and we should continue implementing those as well. Promptly posting slides and videos of conference talks publicly online, and offering a channel for remote participants to ask questions and participate in discussions, can help.?

Enabling and encouraging remote participation can also help reduce , and can help to include the many scientists around the world who rarely travel to international conferences for reasons that have nothing to do with Trump¡¯s policies ¨C such as cost, travel time, or family obligations.

Of course, many of us hope that US travel policies will change after the next election or two. But such hopes have been repeatedly dashed before: witness the seemingly improbable course of events that brought us to this situation. Hoping for a change in the political winds is no substitute for socially responsible and inclusive planning.

At least until Trump¡¯s Muslim ban is actually lifted, it is time for our international scientific conferences to leave the US.

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Bryan Ford leads the?Decentralized?lab at the ?cole Polytechnique F¨¦d¨¦rale de Lausanne.